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Tubes vs Transistors: An Audible Difference?
cgenman writes "Are those vaccuum tubes worth the extra price? This paper, a transcript of a speech to the Audio Engineering Society of New York, indicates so, though the reason is surprising: Overloaded tubes behave better.
While the speech itself is from the early 70's, the paper takes on new importance with the recent trend in louder is better music."
Dollar for dollar, transistor amplifiers output far more power before they're overloaded, making this discussion moot.
If you like the distortion tube amps give (remember, you're not getting the audiophile shound, you're getting "nicely" distorted sound) I'm sure a DSP can do it for you. Even an EQ would probably help.
If you could be told what you can see or read, then it follows that you could be told what to say or think - BoC
The recent trend in "louder is better." Did I just read that? The recent trend? Since the first real Rock and Roll music appeared approaching, 60 years ago now, louder has been better. That's a "recent" trend?
If part of being better includes consistanly sounding the same, then glass audiophiles have to tuck their tales between their legs. Tubes wear out. As they wear out, their sound qualities change. Who's to say that the 'changed' sound is desireable? Maybe it's an improvement...that's the problem; it's not cosistent.
Regardless of which one you feel is more accurate in its source reproduction, solid state devices have the advantage in that they pretty much (not 100%) maintain whatever sound characteristic they start with.
How does a speech from the 70s, discussing how better "behaved" tubes are, have relevance today? Transistor technology has had 3 decades to grow into a more stable, mature platform for audio, and we understand a great deal more about the nature of sound and the equipment producing that sound.
Digging up an ancient speech which probably SPARKED the religious war in the first place is idiotic, in my opinion.
What's next? Will we dig up some argument from the 1880s about the superiority of DC-delivered electricity?
Tube amps are considered more of a "status" item these days... When someone tells you they just got a nice new $300 tube amp, you kind of want to check it out, because it sounds cool...
Better for whom? The average listener won't be able to tell the difference, this is like how theres a few nutbags such as myself that still enjoy listening to vinyl. It can just sound better sometimes.
Also how relevant is this? 30 years ago, we've got all kinds of DSP going on now and very efficient transistor amps putting out a boatload of power before they become strained.
The problem with the louder-is-better issue is the albums themselves. They're mixed horribly. You can play them on a cheap boombox or a system costing thousands of dollars. You'll just hear the garbled shit more clearly on the multi-thousand dollar system.
Presently here, but not there.
The only real place where this has any impact is in recording and performance; amps are frequently overdriven to provide a "fuzzy" effect - guitarists will know exactly what I'm talking about here. There, tubes and transistors sound quite different, and tubes do sound quite a bit nicer.
I'm sick of all the "audiophiles" who claim that a non-overdriven tube amp provides a better reproduction of any given sound than a similar, transistor-based amp. The fact of the matter is, transistors provide a better sound reproduction, as there's less interference from things like the tube's heater or outside magnetic fields. Whether it sounds better or not is up to you, but don't try to tell me that it's a better reproduction.
That's it. I'm no longer part of Team Sanity.
from a 1970's vintage copy of Popular Electronics. When the inputs are overloaded, transistors will clip the input signal with a very sharp transition. Tubes will transition out of the linear state more gradually. A clipped sine wave coming out of a tube amplifer will have rounded edges. This reduces the number and amplitude of high order harmonics present in the clipped output.
That being said, the obvious answer is not to overload the amplifier inputs. But if you really, really like the effect of an overloaded tube amplifer it is easy enough to simulate with a little filtering. (Analog or digital)
If you really want that old "vaccum tube" feel to the sound, try injecting just a touch of 60 or 120 Hz hum into the output.
My rights don't need management.
The record labels want to ruin the CD format
The CD has outlived its usefulness to the labels. They want to move people onto a copy-protected medium so that the MP3 problem is squashed. And think how much better the properly leveled SACD will sound next to the clipped CD.
No, I don't trust in god. He'll have to pay up front, like everybody else.
With sophisticated design, there is little difference between solid state and tube amps.
This assumes that you do not clip the amp.
Most audible differences between amps are due to overload recovery artifacts.
Class A tube amps overload better than class A/B solid state amps.
Tube systems are popular because they are somewhat easier to design and can be sold for more profit to fashionable audiophiles.
One good solution to overload is to buy a bigger solid state amp.
Professional audio systems require a 24dB overload margin.
This ensures that essentially any musical waveform will not clip the amp.
If your speaker requires 1 watt for 90dB of output, for a 24 dB overload margin at 90dB output you should use an amp that will not clip with a 250 watt transient.
Class A tube systems will clip gracefully and you can get away with a 100 watt amp under the same conditions.
I don't know much about amps for just listening to music, but I play guitar and I assure you that you can get much nicer tones out of a good tube amp than from a solid state. I'm sure most guitarists will agree with me that you can definitely tell the difference (though I must admit, solid state amps have gotten much better recently).
I can't speak for the HiFi crowd but when it comes to Ham Radio tubes still have a job to do.
The front ends of receivers ALWAYS behave better when a tube is used because of the gradual distortion that has already been mentioned. On some of the bands that hams use receivers overload easily and the tube characteristics coupled with a high voltage power supply (80 volts or so compared with 12 volts for a transistor rig) can save the day.
Power amps for transmitters are always best when a valve or two is used. There are amps out there that use FETS and exotic technology but if you want to shove 2Kw up an antenna the only way to do it is with some heavy duty tubes.
Ed Almos
Budapest, Hungary
The more corrupt the state, the more numerous the laws. - Tacitus, 56-120 A.D.
While the speech itself is from the early 70's, the paper takes on new importance with the recent trend in louder is better music.
I think when loudness becomes music's most important quality, the word "music" should be placed in quotes.
Really, why care about perfect reproduction when your ears are bleeding?
"You mortals are so obtuse." -Q
I really wish AOpen had more success with their Tube Sound motherboards... If they had released one that supported the CPU I wanted I would have bought one. :(
I am shocked that this old crap has no annotation from the 1990s when phychology tests proved tubes sound more appealing than solid state op-amps.
The reason ?
Odd harmonics vs EVEN Harmonics !!!!
Odd harmonic overtones sound HARSH to human brains and are an unwelcome side effect of all solid state electronic amplification.
That was new data in the 90's that this ancient speech being discussed had no idea about.
Valve amps (the original name for tube amplifiers) are basically voltage driven, so when they distort, even-order harmonics are produced (2nd, 4th, 6th, etc...) while transistor amps are current driven and produce odd-order harmonics (3rd, 5th, 7th, etc....)
I cannot believe at the time i posted this i am still the only one to point this out.
All those years of subscription to The Absolute Sound taght me at least why tubes were better and an oscilloscope visibly points out the harmonics.
The best thing about this, is there will actually be people who enter this discussion thinking they may say something so convincing that everyone will end up on one side of the fence. Fact is, the tube crowd will always swear it's worth the money for the huge difference in sound which they hear, and the non-tube crowd will claim to either be unable to hear the difference, or won't find the disadvantages of tubes (fragility, cost, size) to be worth the minimal difference in sound (as they perceive it). And this isn't even factoring in the vinyl crowd!
Any unintended (i.e. can't shut it off if you want to) effect on the audio is distortion. Period.
Some distortion sounds better than other types. But in the end, you are still getting a signal that is not reproduced faithfully.
(As an aside, modern MOFSETs produce even-order harmonics in an overload situation, just like tubes. This is opposite earlier IC-based gear that produced odd-order harmonics, which are much harder on the human ear. I think this is what the linked talk is going on about. I might also note that audio technology has grown by leaps and bounds since the 70s.)
If you like the "warmness" of a tube, then grab a tube preamp and a modern amp and you can now have the best of both worlds.
The "Audiophile" business is chock full of snake oil, even moreso than many others. $1000/ft "de-ionized oxygen-free" cables? LOL.
Natural != (nontoxic || beneficial)
This article is refering to the fact that when tubes are overpowered, they tend to reproduce the truest sound possible.
Please do not confuse distortion with tubes. Many tube based guitar amplifiers can have their clean channel cranked right open, by use of their power tubes. These tubes keep the sound crystal clear. The distortion is created by the preamp tubes, which are specifically selected based on the distortion you want.
An amplifier warmed up for at least 30 minutes will produce the best reproduction of the origial sound. Many audio professionals will argue that DSP can emulate the effects of these crystal clear sounds and tones. Almost every high end audiophile system includes a set of power tubes specifically because audiophiles _know_ that tubes sound best. DSP simply cannot reproduce the warm tones of tubes.
Asside from the power tubes' wonderful audio characteristics, they can help keep you warm during those late night-mid winter jam sessions... :)
Please know the difference between tubes being used for distortion, and tubes being used for audio reproduction. Also keep in mind that hundreds of tube varieties exist, all with a unique sound.
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Typical solid state amplifiers have increased in power an headroom to the point that you are unlikely to want to listen to them at clipping.
It is certainly true that some people like the coloration introduced by tube amps. Guitar players routinely treat tubes as musical instruments by overdriving them.
Another (non-disjoint) set of people enjoy the coloration and noise of vinyl recordings.
The bottom line is that you can make a digital recording of your favourite vinyl/tube/whatever golden-ears setup, and be unable to distinguish it from the original in controlled A/B comparisons.
If you want to color your music, use tubes. If you want high fidelity, don't.
I once met a guy who was a licensed electrician. He had installed a stereo system is his car. I don't know what the specs were or even what kind of car it was, the thing that stuck in my mind about it was how nice the stereo sounded. Moreover, when he turned it all the way up it didn't distort or hurt my ears, in fact, though it was impractical to carry on a conversation, I didn't come away feeling like I had just stepped off the tarmac at the local airport. Anyway, when I commented about how loud it got, he replied, "I didn't build it to be loud; I built it to sound good." Anyway, that kind of squashed the whole louder is better argument for me.
Better for what? If you like the way tubes distort the sound ("mellow"?) then maybe tubes are for you. Otherwise, if you are after precise reproduction (low distortion, low noise, linear frequency response) then solid state is what you're looking for. All good amplifiers sound alike as long as you don't run them into clipping, that is, if they have sufficiently low noise, distortion etc. All that sound significantly different suck.
this would get an "obvious" tag.
Silcon is too much of a light switch. There is human ear ramping of sound, it is there, it is not.
Plz gain the slightest concept of how an amplifier works. THX
Any audiophile knows that tubes color the sound in subtle, yet significant ways, while for practical purposes and absolutely best reproduction, transistors reign supreme.
A blog like any other.
It seems that everyone here fails to realize the difference between guitar and power amps. Of course for power amps you'd want to have transistors to have as much as power as cleanly as possible and have it be as consistent as possible. On the other hand if you want a guitar amp tubes are definitely a way to go. You get a certain response from them that you just can't get from small silicon squares :). If you ever tried a Marshall's JCM 800 or any other all tube amp you'll notice that the sound changes dramatically as you increase the volume, which in my opinion is a desirable thing for any guitar player that wants to have different types of distortion easily on his disposal.
So the moral of this story is to use tubes on guitar amps since they sound sooo much better although if you plug them into an oscilloscope you'll get some pretty noisy graphs.
"Better" is in the ear of the listener, of course. but, yeah, the "louder is better" argument has been going on for decades.
The answer: Louder is better until the sound is distorted or your ears hurt.
The above does not apply to people who configure sound in their car to play at 120 decibels using the pavement to help modulate the bass. Those folks are after an entirely different sensory experience.
-- Slashdot: When Public Access TV Says "No"
MOSFETs (Metal Oxide Semiconductot Field Effect Transistors) in the article, which are used often today in high power circuits (Car amps definitly do, I don't know about other amplifiers though). They tend to have a better efficiency, and put out more power before they are overloaded (in a sense of how loud the output is. If you just want a very loud output, then just increase power that you use. If it starts to clip, then you MUST lower the input power (ie. the gate voltage on the MOSFET). You can always increase the speaker boltage if you have to. When there is clipping, you are putting DC through the voice coil, which will damage the speakers. As said before, a DSP will do the same thing, only without damaging the speakers (i think, i don't know if it can be done without actually producing the dc).
Whether it's tubes vs. transistors or vinyl vs. CD, it's worth keeping in mind the distinction of "sounds better" vs. "reproduces accurately". You may *like* the sound of tubes or vinyl better, but within normal limits of operation, there is no way tubes or vinyl more accurately reproduce sound than CDs or well-designed solid-state equipment.
As far as the article - the THD levels (3% to 30%) aren't unusual for 60's era equipment. Since the late 70's it's no big trick to design "transistor" equipment that has essentially unmeasurable THD even approaching rated power levels - it just requires lots of feedback and a better power supply than most consumer equipment has.
There isn't much point in observing that tubes clip waveforms more softly when you can design solid state equipment that never clips at all. However, some people may prefer the distorted output of tube amps to the accurate output of solid state amps.
I still use tube amps for guitar ("sounds better"), but all solid-state for playback ("more accurate"). Fender (and probably others) now offer DSP based amps that will emulate tube amplifier sound - haven't ever tried them, so I'm not sure how good they sound.
Tubes are warmer sounding probably because they are richer in odd harmonics. Tubes gradually add distortion as they start to saturate. Transisters are cold sounding, but stay clean until they overloaded.
Not scientific but to my ear the high end with tubes has more clarity and definition to my ear.
"Besides for REAL power, there is ONLY tubes. Look are the linear accelator at Sanford, RADAR, Radio, and TV to name quite a few of real power switching"
Oh yeah! I can't tell you how many times I've been sitting in my living room listening to tunes when I think, "Man, my amp would be so much cooler if it could accelerate protons, too!"
This trend really only came to light in the 90s, particularly the mid- to late-90s. Compression is used to squeeze all the dynamics out of the music in order to make it sound "louder" than the other songs on the radio. It's different from just loud rock instruments. This has to do with the wretched trend of signal compression.
I love reports that tell us what is musically "better". It reminds me of the debate over, of all things, guitar strings.
Some people (Angus Young of AC/DC, for example) swear by using new guitar strings, replacing them as soon as they get a bit worn. Others (e.g. Neil Young) won't use 'new' ones and actually have roadies break their strings in before they will play them.
(Angus also likes to use no effects pedals, while Neil loves effects. Just picking those 2 at random 'cuz I read up on them. Which is better-- straight guitar or with effects?)
Which is "better"? The answer is 'whatever gives you _your_ sound'. You like tubes, go for it! Solid state give you what you want, more power to you!
With amps, people get distracted by engineering gobblygook, but the truth is: to get 'killer tone', you need to choose your own mix. Guitar choice, strings, amps, heads, effects, EQ, there's a fucking reason you can buy a million and one of each-- there is no one right path!
You can't define sound. It's experiential*. There's no one right set of gear. There's no one best type of music. There's no one best musician. There's no best album of all time.
Freebird! Freebird!
*(sonically, you can usually define 'sucky' due to poor audio quality, but when you get into 'good' you start getting into taste as much as specs)
A.
Right, so this ancient study says that when overloaded, tube distortion *sounds* more pleasing than transistor distortion. Well, the true test of a device is under normal operating conditions. Next we'll have something that says tapes sound better than CD's, because tapes have a softer clipping threshold than digital devices (which, for CDs, clip at +32767 or -32768).
Surely no audiophile is going to buy a tube amp because he wants it to sound better when overloaded...for the same amount, or generally quite less, he could get a digital amp with enough power to NOT overload at the given level. But then, some of these (no offense to the reasonable ones) are the people who believe gold connectors "reduce distortion" and "improve sound"...for SPDIF connectors!!
As a Bass Player who has been in on more than a few sessions, I can tell you that my ears tell me that there is a difference between a nice Mesa Boogie or classic tube amp, and a straight transister amp.
I own both types. Both have pluses and minuses. But for bass, you can not beat the tube sound, even sythetic tube is just not the same, the ear knows.
"Who are in control, they are not in control of anything - they don't even control themselves!" - Glen Beck
~jeff
Please stop spreading this nonsense. The vast majority of tubes have MUCH lower distortion than any solid state device. In fact the big DHT's (300B, 845) are probably the lowest distortion amplification devices ever made. Look at the curves if you don't believe me. Tubes at least look VAGUELY linear, transistors most certainly do not.
Solid state competes only by having very high gain and using feedback. There is absolutely no way for solid state devices to compete with tubes in terms of distortion in the forward path.
And feedback has a whole bunch of fun problems. It's great when you're driving resistors or simplified R/L/C 'dummy speakers'... but it has real problems when you drive REAL speakers. Real speakers have dozens of resonances all over the frequency range that throw all kinds of garbage back at the amplifier. Feedback has to take this trash and RE-AMPLIFY THE GARBAGE in order to cancel it out and present a lower output impedance.
With tubes (especially push-pull transformer-coupled tube amplifiers running heavy Class A) you can achieve VERY low distortion numbers with no feedback whatsoever. You do require speakers of higher-efficiency of course, but this is not hard to do. There are very good-sounding speakers in the 95db/watt range and up that can run great on tube amps in the 16w range. Horns up around 100db/watt are happy with much less.
Yes, SOME tube amps sound very 'warm' and distorted, but quite frankly, that was 5 years ago. Things have come a long way. Class A push-pull is really taking off and people are achieving EXTREMELY fast, detailed, low distortion tube amps that have all kinds of advantages over solid state.
Tube amplification is quite alive, even thriving in the guitar world. Despite the many technological advances many would say doom tube amps, they keep making them, and people keep playing them. As a guitarist, where distortion is an important component of the sound in many cases, I find tube distortion more pleasing than distortion boxes or solid state preamps. Even with solid state amps, some will include a 12ax7 preamp tube for the distortion stage.
o m - one of the best in my opinion.
Some of many great manufacturers:
www.soldano.com
www.mesaboogie.c
www.voxamps.co.uk - you can't go wrong with an AC/30
____________________
Peace
SACDs only output in analog because the labels HATE digital output. They think it makes it easer to copy their music.
people who like tube amps also like "super eficient gold plated ultra expensive cables" that shows their stupidity
The best I've found is to import the track into audacity and apply a high pass filter; normally the tracks can put me in physical pain after 30 seconds or so, but after high pass filtering I can have the track looped for 15 minutes or so before I have to change to a less painful piece.
I'm really not an expert in audio, and the above just came from random applying of filters - is there anything better that can be done?
I mod down anyone who says "I will be modded down for this", regardless of the rest of their comment
Do you have any URLs for articles that talk about this phenomenon?
Thanks!
"Almost every high end audiophile system includes a set of power tubes specifically because audiophiles _know_ that tubes sound best. DSP simply cannot reproduce the warm tones of tubes."
:)
Similarly, synth manufacturers have started putting tubes into their products - for example, the recently released Korg Triton Extreme uses tubes to process the sounds. Considering this has an extremely powerful DSP engine, it's doubtful the effect could be used digitally.
That said, some manufacturers tend to use tubes as a "this makes our product instantly better" feature...not always true
Topic 2: The modern loud-is-better trend in mastering. While sadly this is true, it has nothing to do with topic 1. Such music actually is easier for any type of amplifier to reproduce without distortion and clipping, because due to compression and limiting applied during mastering its perceived loudness is higher at the same peak level.
Why the heck do you want to store the data in a RDBMS of all things?
Couldn't you just create a file and reference the file and all other related information from the DB?
Seems that storing and recalling of all that audio information would be fairly inefficient from a DB system.
Then again, I don't know all the angles.
"All those tubes and wires and careful notes!"
This topic is just not news: good audio-amp books that deal with it well have been around for years.i nsley_Hood/searchBy_Author.html .
For example, some really good explanations and designs relating to this topic are given in a series of books by John Linsley Hood, findable at http://engineering-books-online.com/search_John_L
(Some knowledge of analog(ue!) audio electronics is needed to follow some of the points fully.)
IMO some of the information can be summarised like this: Very good amplifiers can be made both with vacuum tubes (or valves!) or with transistors, and very good examples of each tend to sound alike. Some quite subtle distortion issues can arise in transistor amplifiers, from details of the way in which high-frequency rolloff is applied to obtain feedback-amplifier stability against unwanted high-frequency oscillation.
In an earlier life (!) I built/modified some audio amps to JLH's designs, I also decided to choose commercial amps on the basis of checking their design circuitry, (where the manufacturer would agree to disclose it, which not all did), to see if their hf stability circuitry is applied in the way that JLH's design criteria indicate that they should be. Not all high-price audio amps do that.
With examples that do, I found that my ears can (or at least they used to be able to) distinguish what I would call an unforced, neutral, clean sound quality, with undistorted transients, specially audible (for example) in the way that a triangle-sound is left clean and un-fuzzed, and in the way that the sounds coming from the mass of a band or orchestra emerge as distinguishable individuals rather than as a fuzzy sound-mass. Of course, good recordings and input signals
as well as good speakers are needed for any such subjective aural tests, and naturally any amp suffers to some extent if overloaded. It needs also to be noted that the standard that is met by an overloaded tube amp but not by an average overloaded transistor amp is a standard that tolerates a very high and audible level of certain kinds of distortion.
-wb-
Logic, macros, and more
That do not believe in digital anything no matter what the reason. Most of em are just narrow-minded and afraid of the learning curve that goes with change.
I say fuck it -- buy two of everything, plug in, shut up, and rock.
boycott slashdot February 10th - 17th check out: altSlashdot.org
The problem with this is you end up with horrible range that you can't do much with. Loud sounds end up clipped so that the softer sounds can sound 'louder'. Here's why it sucks: You lose a lot of the music's quality. When I turn up this song, my stereo dac becomes the limiting factor. When you turn up crap like this, the sound waves are already clipped. The jokes on them.
People like tube amps because they add a little bit of harmonics that sounds nicer to our ears. Tubes sound 'warm' and they fail gracefully when overdriven. It's an old battle that no one will win, but most muscians go with tube amps so they can't all be wrong
[Fuck Beta]
o0t!
So bloody what. This is not news, it's been known by every audiophile on the planet since the inception of transistors. Transistors clip more harshly than tubes. Tubes clip softly, transistors clip sharply. If you want to go loud without clipping, buy a better amplifier.
Not all tubes are the same. There a in fact only a few tube factories in the whole world and tubes made at certain factories are better than others. It makes a huge difference to the listener. BTW Russian tubes tend to be the best followed by Czech.
By the way you're discussing amps I assume you're referring to reference amps, because there aren't too many guitar amps that 250 watts! As far as reference amps go, there's really no reason to get the $10,000 Manley tube amp.
I'm not going to say that solid state is always inferior to tube, because that's totally untrue. Case in point is the Focusrite Red Range series of microphone pre-amps which have Class A handwired ISA transformers which I believe outperform any tube pre out there. Just the opposite would be a Tube MP from ART is inferior to any of the low end DBX pre's.
As far as clipping an amp, nothing could be more detrimental to your speakers than that. Always get more power than your speakers are rated for. You'll get an overall cleaner sound and won't overdrive your speakers as bad.
Peace
h**p://club.aopen.com.tw/News/News_showAnswer_Old
and.. site with some comments.
h**p://techreport.com/news_reply.x/3670
"No one likes working in a hamster wheel, and your shop smells of cedar shavings from here." - TaleSpinner
Do you work in the snake oil - I mean, audiophile business? I've never heard a bullshit spiel that elegant before. What are you selling?
None of that shit - skin effect, switching time - has any relevance at audio frequencies.
I take it you've already tried the one about the "microdiodes" in wire that make it unidirectional, never mind the fact that the signal IS AC, ferchrissakes?
Ce n'est pas un vrai mouvement de robot!
You make an important point. Good musicians don't want perfect reproduction. They want music. What they want is imperfect reproduction because they want a particular sound that their instrument doesn't naturally give. It's kind of like visual fidelity in movies. It you look at raw movie footage it looks very harsh, kind of like home movies. They have to artivicially color grade it to make it look good. Again they don't want perfect fidelity, because perfect fidelity looks bad. It's the imperfect fidelity that looks good. It's kind of like the old Monte Python sketch in which the american movie director explains that he is shooting snow scenes on the beach because " It looks more like snow than snow."
...is that we have achieved amplifiers based on transistors that are more accurate than human hearing. Once you achieve that, there is no point in having anything else.
:)
Any effect, such as that of a tube amp, a vinyl player, or whatever else makes music better for you, can be emulated. Any distortion, clipping, overloading, whatever.
Audiophiles live in a reality distortion field which makes Steve Jobs (Apple) look like a kindergarten magician.
Call me when TV has the same luxury problem. "This here looks completely real, but some people claim they can see the difference between this and reality. Those videophiles are crazy!". It'll take a lot more than HDTV to do that... and in 3D of course
Kjella
Live today, because you never know what tomorrow brings
But, on the positive side of LOUDER IS BETTER, once we get all of the waveforms totally clipped, then we can switch from hi-fi Class A amplifiers, to no-fi Class C amps, and save a lot of electricity.
Green noise!
Tubes have come a long way as well. Deep Class-A push pull tube amplifiers have very low distortion, zero feedback, very tight & controlled current loops, moderate power (20-30 watts), very low power supply noise, and most importantly, stunning sound.
They also utterly lack the 'warmth' normally associated with tubes, and yet still totally avoid the problems of solid state and negative feedback.
There's been an incredible amount of progress made in the last 2-3 years on these kinds of amplifiers.
As I recall, Don Lancaster had a treatment of how to make a transistor-based amplifier sound like a tube amp...
1) adding hum (60 and 120 Hz)
2) adding harmonics
and so on.
and reference the file
Okay, is there a "file reference data type" in SQL-99?
If I "reference the file," will Seagate/Veritas Backup-Exec [or CA/Cheyenne ArcServe] automatically back up the file when I do my nightly backups of the database [even though, strictly speaking, the file isn't part of the database]? Or will I have to go in and manually configure BackupExec or ArcServe for each file I need to have backed-up?
If I "reference the file," will the database automatically move copies of the file [and/or deltas of changes to the file] to the failsafe mirrors of the database, and/or to the load-balancing mirrors of the database?
And will all of these things be done in an ANSI/IEEE/ISO/whatever sort of a standard, so that if I decide to port my code to a different vendor's product, it won't take me forever and a year to figure out how to do the port?
What I'm asking for would have been SOOOOOO simple if only the idiots on the SQL committee had had an ounce of foresight.
Why are you trying to put the "song" into the database? Store it as a file, then put a pointer into your database. Which is how large digital media automation systems do it. I know of some that are more than 40Tbytes of spinning disks and one that will be in excess of 100T. They use an open standard based system
Perhaps I am simplfying it too much? Or are you making it too complicated.
Tubes aren't as fragile as you might think. All guitar amps and mic pre's with tubes all come with them preinstalled. Rarely will one come from the factory broken, in fact I've never seen that. And these are many times shipped via UPS etc. and we know that packages can be treated roughly.
As far as the "vinyl" crowd is concerned, these guys (and girls) are certifiably insane. Spending the thousands of dollars on home stereo equipment, particularly the $40K speakers and the $20K tube amps, is absloutely overkill. There's a common rule in the audio industry that the sound you hear coming out of the speaker is only as good as what it was recorded on. All these people that tell you that you need this and that are typically telling you to use equipment that specs out far superior to the equipment that was used during recording. LIke all this high end 24-bit/96kHz capable equipment won't help your recordings from 2000 and before, because the standards of digital recording were 16-bit/44.1 or 48kHz. Get something decent and stop sweating what the needle heads say.
Like I said, it all depends on application...
Peace
Peace
With musicians, let's say an electric guitar... the amp is part of the insturment.
There is a world of difference between sound reproduction, and performance.
You like hwo your tube amp sounds with your guitar. It has *nothing* to do with accuracy, or accuracy at high volume, or anything like that; it just makes a better sounding tone.
Any guitar player already knows tubes sound better when overdriven.
----
All of whose base are belong to the what-now?
There have been many improvements in receiver front-end design over the last 30 years, none of which involve vacuum tubes in any way. When in the last time that you saw a professionally designed receiver that used tubes in the front-end? The early 1960s?
Mea navis aericumbens anguillis abundat
BTW Neil Young needs effects to sound better than w/o, perhaps to drown out the incessant one note solos that he's famous for.
Developing a "tone" is so crucial for a guitar player and probably the hardest thing to do. Distinctiveness of sound, even though chords and notes may be similar, is so important. You can tell David Gilmour from a mile away clean or distorted, same for Eddie Van Halen. All premiere guitar guys have that distinctive tone that belongs to only them, this is only achieved like you said by experimenting.
Rock on!
For example, guitar amplification. Solid state just doesn't have that analog "warmth" that tubes do. The funny thing is, you can't buy vaccuum tubes that are made in the US anymore, all the ones I've ever seen are made in Russia. Do they know something we don't?
How's my programming? Call 1-800-DEV-NULL
All of those years of subscribing to The Absolute Sound may have taught you how to discriminate among the various brands and vintages of snake-oil, but they had very little to do with science or engineering.
Mea navis aericumbens anguillis abundat
This whole phenomenon is well understood today. You can buy a little "tube amp emulator", with emulations for famous tube amps. Choose your own harmonic distortion. There are product lines of amp modellers.
Most of the trouble in audio today is not tube vs. transistor vs. digital. It's from artifacts introduced during compression of the dynamic range. The real problem is the car audio listening environment, which is noisy. Radio stations need to sound good in cars. This led radio stations to compress their audio into a narrow dynamic range. People got used to this. Then, when cars got CD players, CD mixes began to be compressed like car audio. ("You don't want your record to be the softest one in the changer"). Now, most popular music is so compressed that musicians have totally lost the musical use of volume. You can't have a soft passage; it will be pumped up. Sharp attacks are clipped, so that tool has been taken away. The end result is popular music that has no texture. Background music.
I think it's a cold war thing. Either because of supply or politics, they never really switched over to transistors and instead kept developing vaccuum tubes which were used in their MIGs. Looks like that expertise has migrated to consumer products.
And sure enough, if you want to hear the ultimate in reproduction from a classical orchestra it is preferable to possess your own concert hall and hire a real orchestra!
The problem with the valve (tube) Vs. silicon debate is that it doesn't relate to the 'average joe' who listens to snatches of music 'on the go' on their radio, CD or MP3 player, probably while doing other things such as sitting on a train, driving their car or working on their PC. Under these circumstances the listener isn't focusing solely on the purity of the sound reproduction but on the 'background noise' that the sound provides with a familiar or favourite tune.
Naturally, a true audiophile will have their own acoustically perfect listening room, will slip on their favourite headphones or sit in front of their favourite speaker system and will wait for their tubes or FETs to warm up - heck no, they'll never turn them off in the first place! Under these circumstances the audiophile will buy whatever they believe will do their 'listening pleasure justice' - tubes, FETs or hybrids. Fair enough - those with the money can do what they want, but the vast majority will be happy with their Sony, Panasonic, PC system etc. and won't give a stuff what actually makes the sound come out the speakers.
In a similar way, the recording industry's attempts to thwart the 'for personal use' pirates with copy protection mechanisms makes be laugh-if I REALLY want to make a copy of something 'protected' and I can't be bothered to find out where to download the latest crack or workaround off the 'net then I'll simply hook up a stereo mike in front of my speakers and make a copy that way - naturally, this won't give me a 100% perfect audio copy but that's NOT going to bother me if all I want is a 'rough and ready' copy.
AT&ROFLMAO
Personally, I wouldn't mind any one of these.
Those are some nice pieces of electronics, regardless of amplifier type.
Izotope ozone is a (non free) winamp/directx plugin that emulates some of the distortion effects that sixties amplifiers produce using tubes. I've been using it for quite some time and it really enhances the listening experience. I can recommend it and it sure is worth the small license fee (which is peanuts compared to what you would need to invest in hardware otherwise). I haven't found any other plugins that produce a similar improvement in sound. There are many plugins that just beef up the bass a bit or add cheap 3d effects. Izotope Ozone is in a different league.
The plugin clearly demonstrates that the distortions (when used with care) can really enhance music. It also demonstrates that you can get the same effect by processing the sound digitally instead of with tubes. Izotope ozone actually goes way beyond what traditional tubes can do because it doesn't have the physical limitations.
Of course most commercial rock and pop music is processed and filtered in the studio before it is put on cd whereas older music (or indie records) tend to sound better when played back on equipment that adds the distortion effects. Of course the amount of distortion is a matter of personal taste and I find that I enjoy my music more with a little bass compression and a bit of sparkle in the higher ranges. Studios tend to optimize for cheap equipment (i.e. it has to sound nice on cheap radios) so you can gain a lot by adding some distortions.
You can also use sound distortion to compensate for lossy compression or lousy speakers. Just boost the bass digitally for the frequency range that your subwoofer can actually handle; add a little sparkle to compensate for loss of higher frequencies during the mp3 compression; add some overdrive on a guitar track. Distortion is not necessarily about reproducing sound as it was when it was recorded but about making it sound as nice/pleasing as possible. Much of the distortion effects in sixties equipment is deliberate and not accidental. Electrical guitars are a good example of how distortion can be used to produce a wide range of sounds.
Jilles
Sigh. This whole discussion is full of lots of opinions from people who don't seem to understand what the paper is talking about, begining with the submitter.
First, the paper is refering to microphone preamps, which are used to boost the very, very low level signals. These signals are affected by impendence, one way that vacume tubes are different that transistors. Both are good, both can be used to make very good gear, both can be used to make very bad gear.
The difference in harmonic orders generated by distortion is important because equipment is often used to intentionally generate distortion because sometimes it's pleasing to the ear. Tubes also begin to compress the waveform when driven into distortion, which often is pleasing to the ear. And sorry, there's no advances in technology that's changed those basic laws of physics/electricity. That's not to say solid state stuff is bad, just different.
Virtually every rock/country/pop CD out there has passed through a selection of vacume and solid state technology. We use the best tools to generate the tone we want, regardless of the technology. If you go to a high quality studio, you'll find that most of the audio monitors are powered by solid state amps. You'll find racks of solid state and vacume tube mic preamps, EQs, and compressors. You'll find lots of tube based guitar amps and very few solid state ones.
An LA2 compressor has tubes and sounds like god on some things. An 1176 doesn't have tubes, and sounds like god on some things. I reach for the one that best serves my needs, not what technology it's built on.
BTW, most real studios don't use the monster cables that audio stores will try to sell you. We use plain old, high quality wire with quality connectors that cost much less than any of the audiophile stuff.
As far as the loud is better stuff spouted in the submission, that has nothing to do with it. You can design a 1 watt tube amp that's very overdriven to get certain sounds at low volume. It's all a matter of knowing what your desired effect is and the purpose, and designing the equipment to deliver it. A 60 watt 4 ohm amp for home listening has entirely different design considerations than an amp designed to deliver 4500 watts 2 ohm for sound reinforcement.
Perhaps you could explain to me, in small words that a musician, studio engineer, and holder of multiple EE degrees (that's me) can understand, exactly what skin effect you are referring to that is perceptible at audio frequencies, and under what conditions.
I'm waiting patiently.
Ce n'est pas un vrai mouvement de robot!
Interestingly enough, valve/tube-powered electronics are also EMP-resistant, which is probably why most Russian military aircraft used them in preference to silicon in their avionics.
The Soviets also have an attitude of "why replace perfectly good old technology with new if it is still adequate". Take the Soyuz capsules as an example.
(caveat: I have no conventionally-recognized qualifications whatsoever.)
Purely as a "thought-experiment", it seems that digitized signals can never EXACTLY reproduce original analog signals, by definition, since they are quantized.
However, whether or not a digitized signal can be brought *sufficiently* close as to be indistinguishable by humans, is a different matter. OTOH, although it's conceivable, it might remain impractical for years, if it requires that the DSP approach the complexity and subtlety of the auditory centers of the brain.
So yes, there are tubes which can handle extremely large (nigh-insane) loads. The tubes might be big, bulky, and made of ceramic, but they exist.
I wholeheartedly agree with the article discussing the Rush album; those waves *were* severly clipped, and whoever mastered that CD should be very very ashamed of themselves (although it looks like the clipping happened in several stages, not just in the final mastering) for forgetting what matters the most in audio production: Quality control of the product by using their ears. Californication of the Red Hot ChiliPeppers lacked the same final check, it's horribly clipped as well.
HOWEVER, As someone with (some) experience in audio production, I should mention that when a signal is compressed and then amplified, this can help increase the detail in weak signals. This is nothing new; in old vinyl recordings, especially of classical orchestras (music with a lot of dynamics) the sound engineer had no choice but to apply some compression to the result.
For digital audio, it is easy to maximize audio levels with any wave editor: Almost every one of them has a "normalize to maximum" function. No harm in that; it allows to maximize the level without clipping it. Typically, gives a result with average sound level of 3-6 dB below 'professional' CDs which is so common to find in 'amateur' demos. The best way to punch up the volume further is by turning it up on the amplifier. However I found my customers wanted the CD itself to be louder. Here's how I did it without causing any clipping.
By itself there is no problem of punching up the level another 3-6 dB, but if you're going to do this by simply increasing the amplitude, the signal *will* clip and sound horrible. Instead, apply a very light distortion over the signal (in cooledit 96 it used to be under the Special menu, draw a slightly bent curve, amplifying softer signals a bit more than the louder ones), essentially mimicking what a tube does. This will increase the average level of the signal, increase perceived definition of the signal, but will not cause clipping. It will color the signal, but in a pleasant way, just like tubes.
This technique does however have two downsides: 1. Because it does color the signal, it may mess up with your carefully balanced mix and equalization. 2. when used to excess, it may still cause unwanted distortion sound. Use your ears to proof the final result. As with all audio matters, don't go for bullshit. Most importantly, let your ears be the judge. And did I mention to use you ears to judge the final result?
Visit http://ringbreak.dnd.utwente.nl/~mrjb/growingbettersoftware to download your free copy of the book
Obviously, someone is unclear on the definition of "recent".
Check out the story of when Dick Dale met Leo Fender and blew up amps on a regular basis.
In walking, just walk. In sitting, just sit. Above all, don't wobble.
-- Yun-Men
You've just proven why a music database would have made a great deal of sense, for your application, or at least, a set of sql functions/extensions like GIS, only applied to your field, with AUDIO64 types being defined, with custom fields like author, copyright, an instruments detail subquery and the like.
YES, YES, YES!!!
With strongly-typed data primitives! [96-bit IEEE Doubles, 128-bit IEEE Doubles, 128-bit LabVIEW TIMESTAMPS, etc.] Or, if they aren't pre-packaged, at least the ability to define strongly-typed data primitives on the fly.
Compare my recent rant:
Does anybody make a product like this???I love my old ~1987 Proton D940. It uses mag-amps. The little reciever checks in at 40lbs.
I wonder why this technology went away. It sounds better than most current ~$1500 recievers.
Get a free ipod.
I've had this arguement with so many musicians with the whole analog tape vs digital, and tubes vs trans for amps, and its really a dead end conversation, no matter what i say, they will swear by the "warm" sound of tube amps and analog tapes, and whatever they say, i will be a strong supporter of digital recording and transistor amps.
my feeling is if you eq your sound right before it hits the speakers, you can make it as warm as you want, and my crate 120 is as warm as i need it to be without having to replace tubes in the middle of a jam, and getting a forklift to carry it around. as for digital recording, my view is "crap in, crap out", so if you dount sound good on a digital recording, you might wanna look at what you're recordng..
none of that is meant to be a troll, its 100% oppinion, and no amount of research, facts, or proof will sway a hard ingrained oppinion. you might as well argue over who's team is the best, or who's God exists. whats the next arguement on slashdot? vannilla or chocolate?
Why are you trying to put the "song" into the database? Store it as a file, then put a pointer into your database... Perhaps I am simplfying it too much? Or are you making it too complicated.
From my other reply:
PS: The things we have aren't technically "songs," although I suppose that our high-speed ultrasounds might qualify as such.Which is how large digital media automation systems do it. I know of some that are more than 40Tbytes of spinning disks and one that will be in excess of 100T. They use an open standard based system
Please, please, please expound.
Who are "they"? Who sells these "digital media automation systems"? What is this "open standard"?
Thanks!!!
Where has the poster been? This argument has been used to defend the superiority of analog equipment from tape to tubes for ages. Hardcore high-end analog folks out there use this argument repeatedly. The main thrust of the argument is that overloading is inevitable, and the relatively graceful rolloff of analog devices/media is always going to sound better than a hard transistor clip.
Personally, I couldn't care less; I prefer the clarity of my recordings not buried in high-end tape hiss or distorted in novel but proprietary ways to try to work around it. And while you can have quality tubes that don't hum, I just can't hear enough difference to justify that much difference in price....
7 November 2006: The day Americans realized corruption and incompetence weren't addressing 11 September 2001
Split the file across BLOBs.
Compare my recent rant:
If I'm in the business of writing file-splitting software to store a piece of 64-bit data into multiple instances of 32-bit data types, then, for all intents and purposes, I'm writing a new computer programming language.Look, it's 2004, not 1984 - all of this stuff should have been done for me by now. I shouldn't have to spend weeks upon weeks of my life writing this kind of crap.
Tube amps are good for guitar amplifiers because in this case the amplifier is going to be driven into distortion, where tube amps sound better. For simply reproducing a recording, however, the amplifier itself is operating in a normal range, and either tubes or solid stae transistors should have similar amplification qualities.
Vote for Pedro
Of course not, but they do contain extremely-hard-to-model non-linear responses of a bewildering variety of kinds. If they didn't, then no one would pay $500+ for DSP emulators like Native Instruments' recently released Guitar Rig, and everyone would just code their own in csound or Max/MSP.
In other words, the software market shows that it takes quite a lot to mimic the sound of classic tube amps (and speaker cabinets, etc.). So, when someone (who actually uses these things on a daily basis, for example) says that tube amps can't be matched by software, they're not necessarily saying there are magical fairies in their tubes (though some meatheaded guitarists might say that), they could be reflecting a knowledgeable point of view on the reality of the current situation.
Personally, since I use these things a lot (I do a lot of home recording) and have seen how they've progressed, I have no doubt that software will eventually match classic tube amp sounds for guitar; it may not even be that far in the future. But it ain't here now.
Shop as usual. And avoid panic buying.
This guy needs moded interesting!
As a side note: I do like "warm" tube amps for certain circumstances. Like my Marshall tube amp of course, which in combination with my Ibanez guitar and a couple DiMarzio pickups sounds really sweet. :)
We all know that bald assertions and insults are worth more then the results of a blind test. Duh.
Idiots or no, you're argumentation style leaves no doubt to your own mental deficiency. Given this, you're probably wrong.
autopr0n is like, down and stuff.
Human consciousness of our senses calls for mixed signals in our technology. Digital precision control of analog fidelity is the best tradeoff. VGA has been popular for that very reason. As is the invitation RSVP. Computers work in the real world, where people make hard choices about sets of nuances.
--
make install -not war
Hmm... except that when shouting in a pipe, the wavelength of the sounds produced by your voice are of the same order of magnitude as some dimension of the pipe. Morever, the shouting in a pipe causes distortion through the Helmholz effect, wherein the pipe resonates at certain frequencies and 'smears' sounds at and near those frequencies. In an audio cable, the wavelength of even the highest frequencies you can possibly imagine hearing (say, 40 kHz per Pioneer's high-speed DAT tests from the '90's) are so much longer than any possible path length difference that the smear... well, lessee. Got a calculator around here somewhere...
The wavelength of a 40 kHz sine wave, in a waveguide (coax cable) whose propagation velocity is 1.5e8 m/s (half the speed of light; a pretty slow waveguide) is approximately 37.5 KILOMETERS. Even if the skin effect presented two paths whose length differed by a factor of four (fairly extreme case), you'd have to have a 25 meter length of cable to achieve 1 degree of phase shift. Summing two signals with phase shift of 1 degree results in a net amplitude loss of 0.00066 dB. One degree of phase shift at 40 kHz results in a time 'smear' of about 70 ns.
Perhaps you have ears capable of discerning a 0.00066 dB amplitude fluctuation at 40 kHz - I know I don't. Perhaps you can hear time smear of 70 ns - I know I can't. Perhaps you also have 25 meter - that's 80 some-odd feet for those of us in the US - interconnects; my whole apartment isn't 80 feet long. However, I think you have none of those things. I think I've presented a pretty extreme case, and shown that electrically, what you claim happens is either not there or is so insignificant that the difference is truly academic.
However, it may be that I've misunderstood your usage of the term "skin effect". It's very common in the audiophile world for salesman and such to misappropriate scientific terminology, banking on the "baffle them with bullshit" principle. If I have misinterpreted your statements, kindly set me aright so that I may further understand exactly what you mean.
There are several manufacturers of very expensive cables who claim that they are directional, and that one specific end of the interconnect must be the source end. They claim that the only way to tell which way the cable is aligned coming off of the roll from the manufacturer is to listen to it, very carefully. They also claim that the cables must be "broken in" through constant listening, and that if you don't use the cables for a period of some weeks, they lose their conditioning and must be "re-broken-in". This is for line-level interconnects, not even speaker-level. They claim that these effects are due to "microdiodes" in the crystalline structure of the copper (or silver) they use for conductors. They cleverly ignore the fact that the signals are AC, and thus current flows equally in both directions. They also totally gloss over the fact that solid-state diodes (at least all solid-state diodes known to real science) have a voltage drop on the order of hundreds of millivolts, which for an audio line-level signal is usually on the order of half of the overall voltage amplitude. It's simply amazing, and sounds perfectly plausible to those who don't know any better.
Ce n'est pas un vrai mouvement de robot!
Note that transients take a lot of power, so it takes a much bigger amp than you'd expect to get truely transparent audio. Big tube amps are insanely expensive, so you're much better off getting a relativly cheap solid state amp that will sound exactly the same.
Being musician, I know that tube mics are very much sought after for recording. Nuemann vintage tube mics especially....
So, it would make sense if people seek to record with a good tube mic, then wouldn't it make sense to want to hear music through tubes?
It's either on the beat or off the beat, it's that easy.
I moderate therefore I rule!
--
No, truly good musicians understand the following:
Perfect fidelity is GOOD, because you can *always* reintroduce the distortion in some other fashion if you decide you want it, but you can't remove it if you don't want it.
You can add a tube processor if you like the tube sound, and the processor+clean solid state amp will sound tubelike, but if you have a tube amp you will NEVER be able to remove the tube sound.
---
Mod me down, you fucking twits. Go ahead. I dare you.
(I read with sigs off.)
Went. That is, in fact, a pretty clear and accurate explanation of skin effect. And it shows me exactly what I already knew. A power difference of less than 0020dB at 25 kHz is, in fact, totally imperceptible to the human ear - at least, according to rigorously scientific studies. Many audiophiles will claim differently, I'm sure.
Additionally, the 50 ns phase shift given in the example is also indiscernible to the human auditory system. In fact, the human auditory system loses the ability to phase lock at frequencies above a few kilohertz. I don't want to go too far afield here, but the study of the physiology of the human auditory system can be interesting. Bottom line is that the spiking rate of the neurons of the auditory system is on the order of a few kHz, and for signals above those frequencies the only information reported is amplitude, not phase. Below, 2-3 kHz, the neurons spike in synchrony with the incoming audio signal. 50 ns worth of phase shift at 25 kHz is inaudible, and I challenge anyone in the world to prove differently. I will gladly eat my own words if anyone can do so - but I'm not particularly worried.
There are, of course, phenomenae that science does not understand or has not yet discovered. However, I personally hold any audiophile results which claim to be able to discern either 0.02 dB of power loss or 50 ns of phase shift, at 25 kHz, to be psychologically biased and inaccurate.
I would hate to refer to you as either being a liar or as being deluded, so I hope that you don't really believe that 0.02 dB is an audible difference. Thank you, though, for a most interesting and polite discussion.
Ce n'est pas un vrai mouvement de robot!
...Like the Mark Levinson 400 series solid-state power amplifiers.
I've read all the reviews in high-end audio magazines and they've all said that Mark Levinsion/Madrigal solid state power amps are one of the small number of solid state amps that can successfully compare against a good tube amplifier.
My old ~1987 Proton D940 uses magnetic amplifiers. The little reciever/amp clocks in at around 40lbs. Sounds better than almost everything available today.
I wonder why this technology quietly died.
Get a free ipod.
Prove what exactly? That tubes are lower distortion? Just look at the curves...
:)
It's easy to try to make it a Tubes vs Transistors argument, but it's never that simple.
Tubes are big, hot, sometimes noisy, inefficient, but above all else, they are profoundly linear devices.
Transistors are EXTREMELY nonlinear. They cannot compete with tubes for distortion without feedback.
So the whole tubes vs transistors debate ends up intertwined with the feedback vs no feedback debate. A lot of the time people will be comparing Single Ended Triode amplifiers to push-pull or differential solid state amplifiers with global negative feedback. Add in the differences in power supplies, and the amps are so incredibly dissimilar that to take it as a basis for comparison between tubes & transistors is insanity.
You can build push-pull tube amps that don't sound 'warm' can compete in terms of power output (for moderately efficient speakers 93db+) and yet have a SLEW of advantages over solid state. Like: No feedback, very short current loops around each stage, orders of magnitude lower high freq noise from the power supply.
You can build solid state amps without feedback (see the Zen) they operate pure Class A single-ended and nonsurprisingly share many things in common with tubes, like inefficiency, high second order distortion, moderate output impedance, and so on... BUT, of note, it will have higher distortion than a tube
Really it comes down to implementation, you can make very good amps with both, and very bad amps with both.
When you try to go for high power and use feedback to achieve it with high-distortion output devices (like tetrodes or any transistor) you tend to do better with solid state because of the higher gain allowing more feedback. Well, that is to say, you tend to MEASURE better on very simple measurements like THD (probably the LEAST audible of all the things you could gauge.) But this is what 99% of amplifiers sold are and some do sound OK.
When you go start to go towards Class A and no feedback or low feedback, tubes (particularly the directly heated triodes) really start to show thier colors. Thier linearity, and the fact that they run at high voltage and low current, lets you accomplish things that simply cannot be done with transistors.
On a day when the real-world news is rife with examples of how faulty information processing has lead to multiple thousands of deaths, Slashdot dredges up issues with studios' technology from the 70's and claims they apply to consumer choices of today. Of course, in the fine print, NONE of the boundary conditions that are pushed, accidentally or intentionally, are similar.
...
Clueless, disingenuous or manipulative? I couldn't tell. But it's not exactly helpful in forming a well-considered mindset about audio design.
Here's my 3-bullet take on the weird juxtaposition:
* The older paper (as well as others quickly linked to) talks about how studios risked distortion by pushing amplifiers past design limits in order to escape tiresome, easily-heard tape hiss. In the 30 years since, the dynamic range of amplifiers has improved (less likelihood for over-the-edge conditions); metering and sound checks have gotten easier and faster, leading to fewer mistakes; and (analog) tape hiss, when it's an issue at all, has also dropped further down the list of concerns. Why is this archive paper relevant without those differences mentioned?
* The second-linked article vents frustrations that even live music is intentionally garbaged up by the creators. The sound is intentionally manipulated to sound "louder" which also makes it SOUND AS IF it was produced by over-driven equipment. That's the artists' prerogative, and the critic's job to carp about. Nothing to see here, folks, except that it interestingly links to
* a previous in-depth analysis of the Dark Side of the Moon SACD that details differences between formats that must have been driven by perceived preferences of listeners, not the formats themselves. Implicitly, some engineers seem to believe that CD listeners prefer LOUD while SACD listeners like "clean," because that's how they manipulated the two formats differently. For CD listeners, they clipped the sound INTENTIONALLY, and differently from any faults of the electronics, in a way that's unnecessary for the CD format. Clipping produces ugly noise on loud spots, but makes the recording sound "louder."
One might guess that engineers aim for the "cleaner" effect on vinyl, too. (Not too many vinyl fanatics risk installing their systems in cars, so they can groove while cruising along I-5, and probably not very many SACD systems, either.) And it's also not too much of a guess to assume that vinyl listeners are about 10X to 100X more likely to use tube equipment, which the owners have selected because it sounds (to them) more the way THEY prefer.
So this attempt at stoking flames under the War of the Formats (Audio Division) can be seen as having nothing to do with "Tubes vs Transistors," as titled. Rather, it oughta be, "my format Rools and yours Sux" or something more appropriate to the information that it provides to the topic. Absent the 2+2=17 faulty logic, the articles actually seem to show that engineering allows whatever "sound" the seller wants to feed the consumer, without any objective "quality" standard at all.
I propose "Troll of the Week" balloting to allow us to heap opprobrium on such posts. This shouldn't even make it on a slow news day. I'm all for vigorous discussion on "stuff that matters" but articles that encourage senseless flame wars don't exactly further that goal.
"Inquiring Minds Want to Know!"
I disagree. Musician's (at least the ones I know) are trying to create a particular sound. When I play cello, I make artistic decisions about what I want my sound to be like. My choice about, for instance, whether to minimize bow attack noise or maximize it is part of my artistic choice. I suppose I could always make bow noise and then filter it out later, but I am a performer not a recording technician. The choice of amplifiers is akin to a choice of strings or pick. It changes the sound in predictable ways, and that choice is part of the music.
While yes it is best to find USA made old tubes, those are either too hard to find or way too expensive.
Peace
Perhaps you have ears capable of discerning a 0.00066 dB amplitude fluctuation at 40 kHz - I know I don't. Perhaps you can hear time smear of 70 ns - I know I can't. Perhaps you also have 25 meter - that's 80 some-odd feet for those of us in the US - interconnects; my whole apartment isn't 80 feet long. However, I think you have none of those things.
/. server blocks my IP until tomorrow which may (ahem) impede my discourse a bit. I do not have a /. account. Thanks for the interaction thus far.
Including the wire in any audio output transformers, coils internal to audio amplifiers, AND in the voice coils of the speakers, surely I do have quite a distance of wire involved in these low-impedance loops.
Again, I'm not selling interconnects or speaker wire OR stating that these alone would make a difference. Perhaps they would, and there are many who adamantly say that. But I'm not suggesting such a remedy. What I'm saying is the differing use of impedance between the typical vacuum tubes versus solid state audio circuits makes a difference. I'm also saying this difference is due to the skin effect, which also happens to be a function of the circuit impedance. I'm also speculating that differences in the the mechanism of switching an electron beam versus a doped crystal junction might play a role.
If my "voice through a pipe" analogy muddled things, I apologize. Certainly that was only indirectly related to impedance and skin effect. However that is the mental image I use, since there can be many shapes and internal textures to a pipe and it is relatively easy to visualize the distortion of audio waves.
PS: I do likely have an anonymous post or two left before the
that most music these days is all recorded and processed digitally, making all these analog sound generation techinques a moot point... except that they let one audiophile prove how much more sophisticated he is to another audiophile. I will stick to my nasty old mp3s, and chuckle when your music collection takes 100000 times more space than mine and sounds no different on headphones. If I want hifi, I go to the goddam concert and hear it live!
Compressing to make sounds "louder" is the same thing that many (most?!) advertisers do with TV ads. They have exactly the same bandwidth and signal to work with as your regular programming, yet they certainly are able to "sound" louder to catch your attention. Same process, different application.
I'm not an expert, so please correct me if I'm wrong.
Some of them are, here's just one maker:
http://www.manleylabs.com/
Tag lost or not installed.
Anyone remember this thing? I never heard anything else about it besides a little picture and comment in Maximum PC Magazine nearly 2 years ago. Are tube preamp boards still in production?
Deltron 3030 - Virus (music video)
... and CD's made more than a decade ago, the old stuff wasn't mastered with all the hypercompression and clipping that almost all modern pop CD's have to have to be contenders in the "VOLUME WARS."
You can make both tubes and transistors sound clean or dirty (distorted), and they do sound quite different when dirty and each is "appropriate" in different contexts, but having whole albums sounding dirty causes ear fatigue and it just sucks.
Does anyone else find it ironic that LP's were recorded with a substantially greater dynamic range than is used on current CD's?
Tag lost or not installed.
Allen Wright (Vacuum State Electronics) is really the only one I know of that will be selling them, though I'm not sure they're avialable quite yet. He's doing differential circuits with solid-state current sinks.
The big leader in this field has been Lynn Olson, you can find info on his amplifiers here: http://www.nutshellhifi.com/triode1.html He doesn't sell anything though. His webpage is amazing, look at everything. I don't think there's anyone that knows this stuff better. He generally promotes 'normal' push-pull over differential because the output tubes are in parallel instead of series then.
Gary Pimm has been working on some push-pull stuff as well. (Just google his name) He did a differential all-pentode amp that achieves something like 10hz - 100 khz flat, limited by the output transformer. OH and it also sounds pretty good too
I think K&K audio has been fiddling with push-pull class A triodes too but nothing available yet.
It's funny to say this is 'cutting edge' since it's really like 60-70 years old, but the revival of this stuff is very recent (2-3 years). Previous to that SET dominated all tube sales. I imagine in the next 3 years or so we'll see more commercial products. The first ones will be from Allen I expect though.
Things were looking bleak for tubes, but between this excitement, and the fact that some REALLY good tubes are coming out of China these days (TianJin/FullMusic 300B's, 2A3's, and even 45's current production are awesome)... well, things are looking up.
Maybe you should have highlighted this part of your post so I will for you: "the big stumbling block is this: you gotta know what transfer function you want to emulate first." Currently, the biggest difference between transistors and tubes is in the "texture" of the sound. Tubes tend to be more "immediate" sounding in the midrange. This isn't a frequency thing, it's not easy to place exactly what it is. The DSP guys have already figured out the distortion and frequency aspects of tubes but they haven't even begun to touch the tactile qualities of them. When someone figures out why tubes act this way, or even a way to reliably describe the effect then maybe we can get those great DSPs to emulate it. As for now, it's about as simple as tubes have it, transistors don't.
stuff that matters.
Constitutional rights may be respected, repealed, or modified; but they must never be ignored.
Peace
Honestly, I'm not well versed in SQL or POSIX-compliant OSes (I'm a Windows programmer by trade), but I can tell you that usually when an datatype is 32 bits in size, it would indicate that the data is set in WORD size chunks. As most processors are 32-bit, the datatype is 32 bits in size as well. So, in other words, I would guess that the BLOB type is dependent on the CPU, and, once SQL gets ported to 64-bit OSes installed on machines with 64-bit CPUs, this should take care of size limitations you are experiencing.
But, like I said earlier, I am likely to be wrong in this regard, and would be curious what truly is causing the size limitation. But, then again, I had to respond due to your comment title.
"Good, Fast, Cheap: Pick any two" -- RFC 1925
when the FCC capped AM broadcasting at 50 kW maximum. And their current (50 kW) transmitter is fully solid state. Lotsa info at http://hawkins.pair.com/wlw.shtml
Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
did /. really just post a speech from 1970?!?!
Geeks play music. Geeks listen to music. We all know that tubes sound better than solid state. Why is this posted here?
seriously
The truth doesn't care what I think.
I am not talking about quantization products, I am talking about amplifier distortion. Any audio amplifier produces distortion along with the amplified signal. If you look at the spectrum of, say, a pure 1000Hz sine wave that has been run through an amplifier, you will also see 2000Hz, 3000Hz, 4000Hz, and so on (in considerably smaller amounts, of course). These are very much audible, and they are impossible to filter out.
The standard test for total harmonic distortion (THD) involves subtracting the input of an amplifier from the output, and measuring the amplitude of the leftovers (distortion and noise). Unfortunately, this test is nearly useless for comparing different amplifiers because it does not show which harmonics are present.
Is this the best we could do? There are at least two instances of the number '1' being used instead of the letter 'i'.
My favorite would have to be at the end of the article, where we find out that the author was predestined to engineering, due to the number in his name...
"THE AUTHOR
Russell 0. Hamm"
As one who spent years diddling with tube amps and the like (long ago during my undergrad years at MIT in EE - NOT CS) I will add my $0.02 - Recorded music - the great majority of it - is severely compromised right from the start due to the amount of data we capture and the manner in which our ears perceive that data. No amount of DSP quite overcomes this present limitation. Remember mono, anyone? Will anyone seriously claim that a monorual recording sounds "realistic"? No, because the spatial components our ears use as cues are missing. Why 2 channels for stereo? Simple - because that was practical in 1958. It has NOTHING to do with having 2 ears, and it too is insufficient to convey the spatial data required to truly simulate an acoustic event. Notice that I have not even yet touched upon issues of dynamic range, etc. as these arguments are not necessary for now. Furthermore, most popular recordings do not use stereo to create a realistic soundfield, but rather a contrived one for effect. So back to tubes - why do some people prefer them? My thesis is that tubes introduce some non-linearities that are simply put "pleasing" in the artificial environment of 2-channel music. The absence of proper spatial and dynamic information in most recordings leaves them open for a degree of interpretation by the listener without reference to any absolute criterion. The upshot is this: current recording technology only allows for a reasonable facsimile of music to be reproduced in the home. Tubes add some color that, under the right conditions, may enhance that artifical experience in an aesthetically pleasing manner. They may make the artiface somewhat more bearable. One could design DSP algorithms that also produce pleasing artifacts. But I think that a better solution is to increase the number of channels captured and reproduced (as Dolby 5.1 almost does, etc.). The problem is that it will take years and millions of $$ for the recording infrastructure and expertise to reach that goal. One cannot simply "generate" multiple channels from a 2 channel source and hope for nirvana. A likely minimum for realistic reproduction is 6 to 8 channels, properly recorded and placed. BTW, I sold all the tube amps I built years ago, along with the tweaky speakers. Now there is a Bose Lifestyle 5 in the living room and it delivers music in an emotionally satisfying way without any fuss or bother. 'Nuff said for me.
Neurons encode information by interfrencing timed pulses on pre and pos sinapses conditions, if the firing rate of the neurons of auditori system is a few KHz, that doesn't mean that nervous systems cannot process faster rates, quite the contrary.
What's in a sig?
I was stating my personal preference, and i was referring to guitar amps.
Solid state has pretty much taken over AM broadcasting at the 50 kW level, but AFAIK, the higher powered shortwave rigs as you describe are still running tubes. CERTAINLY rigs at the megawatt level are.
FM broadcasting is still dominated by tubes, but solid state is starting to make inroads at lower power levels.
Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
Look, you seem to be writing this from the point of view that I've got a PhD that involves both RDBM theory and file system encoding theory.
Now, quite frankly, neither of those "theories" is particularly esoteric, and I could, with a good 3-4 months of study, and a good 3-4 decades of coding, write my own 64-bit database with support for strongly-typed data primitives.
The point is, though, that I have no interest in doing any such thing. I can't re-invent the wheel every damned time I need something. Eventually, at least SOME of this stuff needs to be written for me, or I'll grow old and die trying to write it for myself.
What you've outlined sounds like a great idea for a kid who's got both ten years of his life to blow off and some serious financing from a Sugar Daddy with very deep pockets. But I ain't got either the ten years, or the Sugar Daddy, M-Kay???
And please don't call me a troll. I am desperate for a product like this, i.e. something that can store really large pieces of data, with some tracking of at least the Metadata end of things, and maybe the ability for me to define my own binary datatypes [along with methods to act on those datatypes], and with some coherent integration with industry standard products like BackupExec or ArcServe.
If such a product exists, PLEASE, PLEASE tell me about it.
There must be somebody out there peddling such a thing. What does EMI or Sony use to keep track of the data that they record in their studios? What does Pixar use to keep track of their animation graphics and soundtracks?
I know that Computer Associates used to peddle a product called "Jasmine" that was supposed to do these sorts of things, but one day they just up and cancelled it and left all their clients high and dry [I had to work all the way up the ladder to one of their Senior VPs to find out about this].
I know that Progess Software used to peddle something called "ObjectStore," but it has a terrible reputation, and, as far as I can tell, Progress is letting it wither on the vine in favor of their new financial software initiatives.
I know that Microsoft just announced an initiative called ".NET ObjectSpaces," but, for the foreseeable future, it won't be anywhere near ready to use in a mission-critical environment.
This is something that we who grew up in audiophile families knew all along. I doubt that a technical explanation is even necessary; good tube amplifiers just sound better than their transistor counterparts (although the difference might not be as obvious as with CD vs. LP).
we discovered a new way to think.
...and running it through a decent compressor/limiter stage. There is no real need for amateurs to use crap software these days, there is a plethora of cheap and even free c/l's that rival the "big boys" in quality.
I still use Wavelab 3 which you can probably get on ebay for next to nothing, tc native bundle (ok, still expensive but worth every penny) and the old Waves C1 direct x compressor plugin, I've also got the Steinberg Mastering edition around for occasional use (the loudness maximiser does a good job of making everything "feel" louder if you're in a hurry and the multi-band compressor is useful if you actually know how to use it properly, which I do).
However, there is no substitute for recording at almost the maximum amplitude you can to begin with as when you use a "normalization" or similar function you will also be amplifying any digital or analogue interference in your signal path - often to very noticable levels (especially with entry-level and 'prosumer' kit).
If possible, record at 24-bit and then use a decent resampling algorithm to go down to 16-bit...it will always sound better than 16-16.
I am NaN
The paper was discussing pre-amps, specifically those that couple a microphone to a mixing console. It wasn't really addressing output power during playback. It discussed input-overload and the resulting pre-amp output distortion.
Since a recording engineer has no control over how loud a performer sings or plays into a mic, understanding how the various types of pre-amps handle the peaks can lead to better choices for recording pre-amps.The statement was made that performances recorded via tube pre-amps sounded richer, punchier than those recorded with transistor pre-amps and the article investigated what causes that (the fact that the second harmonic is more pronounced than the third). There was no mention of the playback amplifier.
You were 80% angel, 10% demon. The rest was hard to explain. - Over The Rhine
"Math in a song is good."-Linford
Valves are not linear devices. But if biased correctly, they can approximate linear behaviour. My grandpa was a big cheese in Mullard valves... Sadly not the winners in the thermionic war but they had the best sounding valves ;-)
In the late 70's the Navy used 500 watt tube McIntosh amps to power the noise generator on submarines during excercises. We played tapes of russian boats for war games. One time we got the key to the enclosure and borrowed it. Took it to a guys home and hooked his stereo to it, and pumped it through some Bose 901's. You have never heard any sound that clear. The res of his system was high end Harmon Kardon, Sansuei, and nakamichi.
Professional Politicians are not the solution, they ARE the problem.
Honestly, I'm not well versed in SQL or POSIX-compliant OSes (I'm a Windows programmer by trade), but I can tell you that usually when an datatype is 32 bits in size, it would indicate that the data is set in WORD size chunks. As most processors are 32-bit, the datatype is 32 bits in size as well. So, in other words, I would guess that the BLOB type is dependent on the CPU, and, once SQL gets ported to 64-bit OSes installed on machines with 64-bit CPUs, this should take care of size limitations you are experiencing.
The problem with SQL [like all the ancient languages, such as BASIC, or C] is that it doesn't have a good sense of datatype. Practically everything in SQL is little more than ASCII [and often only the first 7-bits of that].
A 2^32 byte BLOB is just that: 2^32 bytes, i.e. 2^32 single-byte ASCII characters.
Boy do I wish there had been some honest-to-goodness "scientists" or "engineers" or "mathematicians" around when these languages were being invented. Instead, we had a bunch of ivory tower morons who were trying to create some kind of abstract "natural" language, un-encumbered by what "scientists" and "engineers" and "mathematicians" [and recording studio geeks] really need, which is data with a strong sense of type.
How neurons encode information is NOT - repeat, NOT - a known process. There are several theories regarding whether coding is purely based on spike frequency, spike synchrony, or some other coding systems we haven't discovered yet. I've spent the last two weeks listening to some of the world's brightest and most knowledgeable experts on neural coding, auditory system, visual system, etc at the Telluride Neuromorphic Engineering Workshop and the best thing that can be told is that there is more going on than spike rate, but there is no consensus on exactly what that code is. If you know more and better, then you should be here next year. Contact the organizers.
What I DO know, and what actual experiments have shown, is that auditory neurons fire in synchrony with the incoming audio signal up to a few kHz. Beyond that, there is no correlation between the phase of the incoming audio signal and the spike train from the neuron. The neurons continue to fire, but not in phase with the audio signal. Of course higher frequencies are being detected and passed on to the brain; but absolute phase information, as far as anyone can tell, is not preserved beyond that few kHz limit. Again, your evidence to the contrary is welcome. Try to be specific and cite research wherever possible.
Ce n'est pas un vrai mouvement de robot!
No, the point is that if you could reliably add the bow noise back in later with no change in sound, would you want to make it and record it with the bow noise included, or would you want to not make the bow noise and record it clean, with the ability to add it in later? I've run into this with musicians, especially guitarists - they set up their stack of effects and say "This is how it needs to be recorded". Since I like recording, I just do it eventually, but I always try first with "try it clean, we can run the clean sound through the chain later to add in your effects, but starting clean gives us more options". Sometimes they listen, and they're rarely sorry.
Bow noise is somewhat different, in that its more about *playing* than the output. A closer analogy would be the choice of microphone used if you were miked for a performance - would you want a mike that changes your timbre, or would you want a neutral mike? Obviously, the neutral mike would be preferable - coloration and alteration of sound should *always* be intentional. Amps are not equivalent to bowing style, to strings or to pick. The purpose of the amp should be to make it *louder* without changing timbre, tempo, or any other quality than volume. If you want a particular tonal quality to come through the amp, it should be provided by something that is intended to make that tonal change. A box that changes tone is not an amplifier; it's a sound processor.
Further, audiophiles are rarely musicians; their choice is a lie, because they talk about 'transparency' while seeking a non-transparent sound. They talk about being 'true to the original' while seeking to change the original sound. Changing the sound to be pleasing to your ears is fine, but don't try to justify it by saying you're trying to get as close to the original as possible.
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Mod me down, you fucking twits. Go ahead. I dare you.
(I read with sigs off.)
When you're done playing with all that BS, and maybe getting yourself some thousand dollar speaker cables (and a thousand dollar power cable to go with them) you should check out douglas self's amplifier design book, or at least wander around his website.
The whole anti-negative feedback thing held onto by tube fans is largely a load of crap. I'd love to see the results of some double blind testing, but generally these people are totally uninterested in that sort of thing (a sure sign that deep down they at least suspect that they're imagining some or all of the results)
Actually here are some simple double blind tests that are fun to look at.
Look at the descriptions for why some of the amps were discernible from the others. I still think the speakers are far and away the most dominant effect for how a system sounds, assuming no pathologically weak link elsewhere in the chain.
Might as well buy a decent amp of adequate power and focus on the speakers if you really want to have better sound. If you are more concerned with convincing yourself that you have better sound, spend the money on whatever floats your boat.
The poster uses in his sample figures 24 bit, 96 ksample recording. I understand that recording like this is done for mastering audio CDs and other studio processes. OK, so I can see wanting to work with that as your medium.
The poster then refers to this as "medium quality sound" and laments that he can only store 2 hrs of it in a (file/object/dataspace?).
The poster follows this up by declaring that 32 bits are worthless and that he needs 64 bits. The discussion at this point is computer / database and maybe I don't understand. Does the poster require the ability to record regular audio with 64 bit precision? Every bit doubles your resolution, and you want 40 more of them than are available in studio master recordings?
Okay, imagine you're the recording studio geek. Say you're in charge of recording the latest, I dunno, Sting [ex-Police] album.
Monday AM. The drummer comes in, and you record two channels [i.e. stereo] of his riffs. Recording Time: 4 hours, Data Size Total: probably in excess of 8 GB. [But at $0.05 per gigabyte, who cares?]
Monday PM. The bass player comes in. 4 hours, 2 channels, another 8 gigabytes.
Tuesday AM. The lead guitarist comes in. 4 hours, 2 channels, another 8 gigabytes.
Tuesday PM. The pianist comes in. 4 hours, 2 channels, another 8 gigabytes.
And so on, and on, and on, over the course of weeks or more: The lead singer, the backup singers, the violins, the mandolin, the bongos, and who knows? Maybe Yo-Yo Ma will show up with his cello.
Point is, you're generating absolutely massive amounts of data, and you've got to have somewhere to put it. Unfortunately, the industry standard language for database access, namely SQL-99, can't support anything larger than 2^32 bytes of data in any one place, so you're just overwhelming this antiquated language.
What you need is a language [in combination with an architecture] that allows you to address your data in 64-bits, rather than 32. You also need a coherent database product that puts all this stuff together, so you can move it from your client workstation to the server, and mirror it to your failsafe redundant server, and make nightly tape backups, and keep track of just what the hell it is that you've been recording [with what's usually called "Metadata"].
Similar problems are faced by pretty much anyone else in the content creation business [such as the animation guys at a place like Pixar, or the particle physics guys at a place like Fermilab]: How do you keep track of these massive amounts of data that just overwhelm ancient paradigms like SQL?
Perhaps I misunderstood that part. But I'm pretty sure that 24 / 96 recorded audio gets filed under the heading of 'high quality'.
Right now, that's pretty much where the industry's at as a standard for the recording of audio performances [although the audio recording industry has a Moore's Law just like everybody else].
But if you're doing something a little more scientific-ish, like high-speed ultrasound, then 24 / 96 is at the low end of things.
Who cares if a tube or transistor amp sounds better. My hi freq hearing is shot anyway, so it doesn't matter LOL. Comes from listening to LOUD music back in the 70's.......Rockin' on an 8 track tape player and 4 6X9 coaxial speakers cranked up too loud and too much distortion......ahhhhhhhh those were the days. LOL...... Seriously, I used to love the old glow of a tube amp, lights in the room off, that nice orange glow coming from the back of the amp.....
Well if you have some leftover ECC83, ECC82, ECC81 and EL34 I may buy them :)
``If a program can't rewrite its own code, what good is it?'' - Mel
It's funny to see the myth about the cost of tube amps and preamps on slashdot.
Check out bottlehead.com and see a very good tube preamp for cheap.
There are tons of schematics out there, were you can build a cheap amp. Cheaper than Best Buy junk.
In the world of guitar amps, where at least part of the signal path is often overdriven (nice crunchy sound) your point is completely accurate.
You could have eliminated this confusion by perhaps inlcuding the word "guitar" somewhere in your post.
Don't take this the wrong way-- I'm a practical bang-for-your-buck sort of guy. But don't confuse tube amps used for audio replication (like in your home stereo) with those used for performance (like in a guitar amp). In the latter case, the tubes and the amp are themselves part of the instrument, and part of making that sound what it is-- feedback, distortion and all.
That said, after that lovely guitar/tube amp sound is recorded somewhere, I'll be playing it back on a nice transistor rig at my house. Because at THAT point, all I want is accuracy. Affordable accuracy, as I use it to cleanly reproduce distortion somebody else made.
Two separate things: amplifier as instrument, and amplifier as sound playback device.
... it is my understanding that tubes will sound better, given that anything with transistors will no longer work.
You can emulate valve clipping with a couple of small FETs and a handful of passive components per channel. It's basically just soft clipping, although it's easy enough to add in some hum (high-value resistor and capacitor from the top of the power supply's main rectifier, assuming a series-regulated or similar PSU), and white or pink noise (capacitor from the top of an unfiltered zener diode).
Or you can get silly about it and emulate the valve clipping and noise in each stage of the amp instead.
Got time? Spend some of it coding or testing
Get a cheap tube amp and put it somewhere in your audio path. Of course, the DSPs are kinda nice in that you can simulate a wide range of products with them, and they don't break...
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
High quality analog processing has a very special type of warmth and compression. It may be subjective to many, but I suspect this is mainly among those that have blown their ears out listing to stuff at too high a volume.
If you don't have a soundcard with a Crystal Semiconductor codec, you're probably missing out. ;-) Some (not all) chipmakers are up to the task.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
i bought a marantz 1030. 2004, i use the same unit to run sound from my emu10k1. it still sounds nice. it powers two homemade speaker enclosed dual coned automotive walmart on sale i forget who made em speakers. the 1030 is prone to intercept cb radio transmissions, and that gets annoying as i live nearby a heavily travelled truck route. it's only 13 watts RMS, but itsa quality 13 watts. it's as close to a tube amp as i'm gonna ever get.
Serenity now, insanity later.
a lot of the non-tube equipment tends to have a short development life-cycle. So by the time you're equipment starts acting wonky, the replacement will probably have a few extra features or improvements.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
Water cooling can be a disaster. And it's expensive. And it's a pain when you want to make upgrades to your box (which is assumed since you already are modding it).
I'm hoping the new BTX will get people to reconsider thermal management. Someone needs to take a hint from laptop designers... heat pipes, consolidated radiators, and one or two fans, tops.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
It's actually a pretty disgusting trend in professional audio as well.
b je ctv.htm#1
Manufacturers offer up specifications for their equipment based on the demand for perfectly linear, zero-distortion amplifiers and signal processing equipment. However, all the reviews then go back and say that the sound of a particular distorted source is preferable. At that point, there's really no point in providing a zero-distortion signal chain. Any distortion it produces would be very well masked by the distortion of the source material.
Here is the best source I've read on the subject:
http://www.dself.dsl.pipex.com/ampins/pseudo/su
Please don't slashdot him, I really would like to be able to offer this link to others in the future.
~Loren
SACDs have an internal DAC. I'm pretty sure it's clocked at 48kHz at 20-bits dithered down from whatever interemediate format is used during the decoding of the SACD track.
If you could pull a 16bitx48kHz digital signal out, I think you'd be pleased with the results.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
I just got home from the studio, laying down some tracks, and just had a similar conversation with the recording engineer. I've also designed and built custom tube guitar amps. The reason tubes sound better to the human ear, is that when an amp distorts, both odd and even harmonics are produced. Odd harmonics sound harsh to the human ear, even harmonics tend to sound more 'musical'. When a solid state device clips (distorts), the waveform is cut off sharply, creating more odd harmonics than the more rounded clipped waveform produced by a vacuum tube. Also, the output transformer in a tube amp tends to cancel out odd harmonics, and even more so in the common push-pull type output circuit. I've had numerous chances to sit down and try some of the best/latest DSP-based amps and processors, and though they have gotten worlds better in the last 10 years, they still aren't 'there' yet. As far as for musical instruments and home stereo (Try playing a CD through an old MacIntosh amp with the folded horn speakers for a treat!) tubes definitely sound better. Now, for things like car stereo, large P.A. systems, etc., or if cost/weight/power requirements or heat is a large factor, solid-state amps are the way to go. BTW, the recording engineers' state-of-the-art mobile recording setup I recorded through tonight had a whole rack of vacuum-tube preamps, and was one of the things about his rig he was proudest of!
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
In the professional recording studio, that is, not some guy who has some digital recording equipment and a hard drive, the date goes onto tape through a Nagra digital tape drive. What you're talking about is strictly low budget, small time audio recording. If you're actually talking about recording audio, you'd better be using tape, at least until it's time for editing and mixing.
Tell that to these guys:
Or to these guys:As opposed to just accelerating electrons?
http://www.superaudio-cd.com/technology_explained/ detailed_information/whitepaper.pdf
Find me that 48khz 20-bit DAC you're so proud of...
which is to be expected. I didn't know CS4397s came so cheap nowadays (being used in the high-end Marantz player). ::shrugs:: Still, my point still stands. You could output that using an optical out (the really high-end Phillips player supports that), and that's at the full 192kHz.
No one says you had to dumb it down to SPDIF.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
Actually, they use tube amps..tube preamps and tube microphones to be exact. Just google for professional audio recording studios, and look at the equipment they list. If you're refering strictly to audio power amps, then yes, they mostly use solid-state amps to drive monitors and headphones. But just mention a vintage Neumann U87 tube microphone to any top recording engineer, and watch him drool. Clipping isn't an issue here, but dynamic range and attack/decay characteristics among many other factors add up to produce a huge difference in the hard-to-define 'feel' of the sound.
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
The other significant factor here is the way in which tubes go nonlinear, or distort. They tend to gently clip the wave increasingly as the input gain increase, whereas transistors tend to just go into a full clip mode, and you get a nasty buzzsaw effect.
If you feed your undistorted guitar sound into a digital audio recorder, you can apply any waveshape function you want during mixing. I tend to prefer the soft saturation of an arctangent, but I know others who like the harsher sound of piecewise -1.0 to sine to 1.0. For a real fuzz use sine past its maxima.
I also remember reading that solid state distortion tends to generate odd order harmonics, and tubes tend to generate even order harmonics, (which are considered more musical or less disonant)
It's easy to get the even harmonics back: just make the waveshape asymmetrical, that is, make the positive half of the waveshape different from the negative half. For example, add a bit of DC to the signal before feeding it to a symmetrical waveshape such as arctangent.
Of course, the delay inherent in DSP favors an analog waveshaper such as a tube amp for live performances.
Sure, they distort elegantly, but when driving them at reasonable levels, distortion should be negligible
For those playing at home, "reasonable levels" for a final mixdown are nowhere close to the same as "reasonable levels" for an electric guitar. You seem to pick up on this next:
any "desired" distortion should be in the hands of the producer/mixer.
And some producers would claim that a typical tube distortion box will color a guitar's sound better than a typical solid-state distortion box.
Thanks! I'm looking over Caché as we speak [although I really oughta go home and get some sleep - I gotta be back here in just a few hours].
If you can think of any other names, please post them.
Thanks again!
That is a very, very nice link, by the way.
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Mod me down, you fucking twits. Go ahead. I dare you.
(I read with sigs off.)
I can easily see that there would be less inertia involved in switching a beam of electrons than there would be with changing the saturation levels across multiple junctions of doped solid silicon.
Sorry, but that whole rodomontade just got funnier and funnier as it went on, and that last sentence cracked me up.
Having studied microwave transistor structures in both Si and GaAs, I can tell you that at audio frequencies, "intertia" of electrons, perhaps you want to mean dispersion or diffusion current velocities, is quite irrelevant until you start going into the 100s of MHz.
Yes, a legitamte concern with BJTs is time taken to discharge the newly formed "capacitor" at the reverse-biased P-N junction. No, this does not make BJTs useless, it just means you have to be smart about your circuit design - make sure there's enough current to drive the base as fast as you want it.
And, I'm sorry to sound snide, but what exactly about a high impedance circuit "favours" voltage over current? I'm no valve expert at all, but I was under the impression that valves were voltage devices! An ideal thevenin equivilent voltage source should have a low impedance!
Honestly, I can't believe so many people think audio is some kind of black voodoo magic. Try designing the frontend/filtering/amp stage for a GPS reciever, or carefully calculating intricate patterns on a PCB to create matching transformers for GHz signals using nothing but the shape of the copper!
Well, maybe is not a fully know process, but as you seems to know, there's a of lot work done in that area, and my expressed opinion is quite common in the field, so I don't understand why you try to emphasize firing rate as a limiting factor.
Of course higher frequencies are being detected and passed on to the brain; but absolute phase information, as far as anyone can tell, is not preserved beyond that few kHz limit."
I've never pretended that phase information is preserved, just that is not irrelevant, quite the contrary.
Again, your evidence to the contrary is welcome. Try to be specific and cite research wherever possible.
Easy, take a look at the work of Liaw and Berger on adaptative synapse simulation.
Now, could you please indicate some research work that provides some facts about the limits of neuron firing phase shifts effects?, Note that the work I've cited specifically adresses that point, and strongly (succesful and patented simulations) suggest the contrary,specifically read the work on computational capabities of pre and post adaptative synapse behaviour.
What's in a sig?
I currently own a $1,400 solid-state (read: transistor) headphone amplifier to drive my HD650 headphones, a custom headphone replacement cable, and I use a RME 96/8 PAD soundcard ($400 retail). There is an obvious difference between tubes and solid state. On the high end, a $3,000 tube amp is likely to sound "warmer," or more "liquid." This stems from two things, primarily. When tubes distort, they produce clipping on even-order harmonics, especially the second, which adds to "body" or "fullness," and this is extremely obvious even to an untrained listener, when listening to two high end pieces of equipment side by side, one tubed and one solid state. Solid state amps tend to produce distortion on odd-order harmonics, especially the third and those at extremely high multiples relative to the fundamental; this creates the "cold," or "icy" feeling that a lot of solid state amps have. I own one of the most powerful small-output amplifiers on the market in terms of sound quality; total distortion is literally zero and it possesses something like a -130dB noise floor (see www.headphone.com for more info). Look at guitar amps. Good guitar amps are always tubed for this reason: overdriving a vacuum transistor (a tube) produces these full bodied, rich, beautiful harmonics, whilst solid state just never seems to sound right, and in most cases sounds downright wretched. This is old hat to a lot of people. Worthy of posting on slashdot, although the article is ridiculously verbose and poorly demonstrates differences between the two; it is more of an objective analysis. -Foo
There is a vibrant community of hobbyists and it's turned out to be a lot of fun!
Nothing in the world is more dangerous than sincere ignorance and conscientious stupidity.
And after the sound engineers have done their damange, the radio stations try to do the same type of compression again during broadcasts, effectively squeezing out a large portion of the range.
Even starving artists can maintain the integrity of their work. Nobody chased after [Insert Your Favorite Artist Here] and decided that those shadows needed to be lightened and that the yellows are too bright.
But all that aside, I'm not sure I've ever seen a watercolor with much depth. Using your 'logic' the tube amp is the equivalent of painting anything in oil because the oil (tube) paints add their own depth to the painintg (music). Music changes the world, paintings only try to freeze it. And please don't try to mix metaphors. You wouldn't mix peanut butter with mashed potatoes would you?
[Fuck Beta]
o0t!
>> That is a very, very nice link, by the way.
Indeed it is. I wrote a few papers in college about musical psychoacoustics and how bizarre the opposing results of the research turn out to be. This guy, however, is the only source that I've read that shows a truly logical, scientific approach to debunk the audiophile mentality.
I hope that there's enough readers on this thread that actually read the entire paper and can understand it.
~Loren
The problem is that audiophiles are rarely smart enough to understand the research that refutes their bullshit. Then again, I suppose that if they were smart enough to understand it, they'd stop paying thousands of dollars for cables.
Reading that paper brought back fond memories of my acoustics professor, who one day brought in a hand built 50W solid-state amp and a (borrowed) tube amp, hooked it up to a very nice set of monitors, and proceeded to prove to the students that the only differences they could hear were in their heads. Especially when he started bringing out his measurement gear. I think he might have had a subtraction rig setup at one point too; it's been a few years.
---
Mod me down, you fucking twits. Go ahead. I dare you.
(I read with sigs off.)
I love tubes. I've actually had dreams about tubes. (seriously!) Energy wasting clumsy things that they are, I think they are great. I enjoy watching them glow and have for may many years.
:-)
I appreciate listening to a radio program more if it's from a tube radio. To me, it "sounds better" because I appreciate it more. If I were blindfolded and was lead to believe a certain radio was tube type and another was solid state, I might perfer the tube set even if they were actually both solid state.
As far as long lasting, you'd be surprised how tough tubes can be. It's usually capacitors that wear out before tubes. Tubes survive things such as sun spots or electromagnetic interference much better than transistors too.
I for one wish more consumer electronics were tube based. Maybe it's the construction, but an old tube radio was built *way better* than any of this mass produced, cheap crap from China.
I also think that food cooked in a cast iron pan
is better than teflon. I like dumb terminals, digital clock radios with mechanical dials and analog meters with physical needles, not the digital LED crap.
Oh yea, and I perfer a command prompt to a mouse any day.
In the beginning it was LP versus CD. (Nobody mentioned cassette, except to ask how come a bootleg recorded from an LP on a 99p ferric cassette using a 49 quid midi system sounded better than a store-bought original.) Now that the recording companies have all but killed off LP, hi-fi bores (if I called them "audiophiles" there would most probably be a mob of News of the World readers standing outside their homes, waving placards and pouring petrol through their letter boxes) need something else over which to disagree.
So we're back to silicon vs. vacuum. Now, in the 1960s and 1970s, transistors were still just expensive enough that they were still competing with valves, and a tranny amp from that vintage -- if it's been fitted with new capacitors, which degrade over time -- will sound as good as a cheap valve amp from the same vintage. It had to, because the competition was there. Today, valves are strictly in the realm of esoterica, and modern IC / transistor kit doesn't have to try to compete with them.
But it's a highly subjective area, and "scientifically perfect" reproduction (identical waveshapes, just different amplitudes) is not necessarily right for the ear. There is little doubt that the distortion characteristic of transistors is harsher than that of valves. This is because, by trying to be "scientifically perfect", they hit the supply rails easily. (Recall that valves use supply rails between 100-500V and require transformers to match to low-impedance loudspeakers; transistors are driving the speaker directly, 20W RMS at 8 ohms is 36Vp-p or +-18V). So with valves, there is more headroom. Deliberate slew rate limitation also helps, by giving a different type of distortion (never quite making it, which gives even harmonics, rather than trying to overshoot and maxing out, which gives odd harmonics). Odd harmonics are reckoned to have a harsher sound than even ones. In fact, modern op-amps, with almost DC-RF bandwidth and consequently slew rates in volts/nanosecond, are as harsh as you'll get.
Bottom line, if somebody spent a fortune on an amplifier -- beyond the point where the Law of Diminishing Returns sets in -- they must think it's good, otherwise they wouldn't have bought it. And there's unlikely to be any way of convincing them any different.
BTW, the first commercial use of transistor power amps was in juke boxes. My dad has a 1962 Seeburg with a 25+25 watt power amp (transformer coupled, has 100V line outputs, C/T to chassis so you can easily arrange mono speakers, taking 1/2 of LH signal plus 1/2 of RH signal in series) and also a power oscillator to run the motor at 45RPM (it does 33rpm on 50Hz so it needs 68Hz for 45RPM; it actually cheats by starting at 33RPM then switching to 45RPM, so it doesn't need to cope with the starting surge. A stationary motor looks like a short circuit). I don't think this was the first juke box to have a transistor amplifier, though, because I've seen one in a 1957 Wurlitzer (but this may have been a retrofit).
Je fume. Tu fumes. Nous fûmes!
Well, a long & drawn out old debate. First off; As that article is from the very early 70's, it doesn't really apply. Transistors from those days *did* suck & *did* sound bad. In one post, someone mentioned F.E.T's as a viable alternate to tubes. True, but expensive & very vulnerable to both static & the nast cascade effect should the input of the amp go pop. Second, tubes don't have crossover noise at all. Much more like a dimmer switch. Like FET's as well mind you. Sure they colourize the sound when distorted. Any amp would do this regardless of it being either tubes, transistors or FETS. All really irrelivant. Personal preference as the specs can be great depending on the way its tested. Who cares what type it is as long as the listener likes it. Thats all that matters.
Vermeil is a technique used for jewelry: gold-plated silver. Then you have the conductivityof silver with the corrosion resistance of gold. Or perhaps they could do platinum-plated silver? Platinum is more corrosion resistant than gold.
You might want to narrow your sweeping indictment there. I run a pair of homebrew tube monoblocks (4X 6550 per channel), and you won't find any "gold plated super mojo cables" in my system anywhere. The patch cords are mostly homemade from RG-58 coaxial cable, and the speaker cables are 14 gauge zip cord from Home Depot. :)
At least the homebrew/techie users of tubes are generally knowledgable enough to avoid the audiophool snakeoil out there. Many of us make a living in electronics design, afterall.
The Tube vs. Transistor sound debate is subject to too many variables (source material, speakers, room acoustics, individual hearing variations, etc.) to make a solid pronouncement on one side or the other. There are great solid state amps and shitty tube amps out there.
To me, the primary advantage of tubes is aesthetic (can't beat the warm glow in a dark room!), and the utter simplicity of the circuit designs. After working with semiconductors all week at work, it makes a nice change to work with "retro" technology as a hobby. A polished metal chassis full of heavy iron and glass bottles has a "soul" that the black/silver plastic riceboxes from Best Buy never will.
Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
this distortion effect went under the name of "transient intermodulation distortion" and had to do with the "hard clipping" of transistor tech vs. tube tech. I remember reading about/seeing this in the early 80's....
Tube amplifiers do indeed use negative feedback
Audiophile single ended tube amps do not have any form of global negative feedback. True, some push-pull designs do have it. These are generally not high-end audiophile amplifiers.
As mentioned, tubes do, it's just local rather than global
I know, I was a little sloppy with wording. Local negative feedback does not cause any of the problems that global negative feedback presents. The main issue is that some of the low-order distortion from the output gets fed back into the input, gets distorted again (due to the limited speed of the amplifier), and becomes high-order distortion. This does not happen to the same extent with local feedback.
Wrong again. Tube amps do produce high order harmonics
In a recent issue of AudioXpress, there was a paper from someone who did some distortion analysis on about 20 different amplifiers. Transistor amplifiers had fairly "rough" distortion graphs, and distortion levels were almost the same up to about the 8th or 9th harmonic. Tube amplifiers had much higher levels of 2nd and 3rd harmonic, but didn't have almost anything past that.
I would rather have 200 Watts at 0.002% THD solid state than 10 Watts at 5% THD tube (similar price range), since the former tells me whats actually being recorded.
Well, that's where your goals diverge with those of audiophiles, most of whom want to listen to music the way it is supposed to sound live. After all, if your system makes a recorded tuba instrument like a real one, who cares what THD numbers it has?
These are a series of articles written by Douglas Self (an engineer who worked for SoundCraft), published in Electronics and Wireless World over the last three decades.
Well, he is the father of the 1970s thought movement I was referring to. I do not happen to agree with his reasoning. The goal of audio reproduction is not to please a distortion analyzer, it is to please a human.
Measuring THD to determine sound quality is like looking at file size to determine the quality of a compressed sound file. Objectively, you lose more information if you compress a CD to a 192Kbps MP3 (100MB of raw audio -> about 8 MB) than if you resample it to, say, 22KHz (100MB -> 50MB). After all, the 22KHz recording is still 100% accurate, we just lose an octave or two; in comparison, the MP3 file is much less accurate. Nobody would use MP3s to store, say, a signal recorded from a nerve (which happens to be in the audio region). But the MP3 file will most certainly sound better than the resampled file. Why? Because humans don't perceive everything in a sound file the same way. Sound reproduction is not about accuracy, it's about human perception.
This is why, as stated elsewhere, some people consider the guitar amp part of the instrument. It's like violins. You can get a violin for $100, or you can try to get a Stradivari for under a million.
Some instruments have variable sound boards that let you do with wood what you do with an amp, alter and amplify the sound in various ways.
Besides, for most of us who don't play electric guitar or are in a band with one, our only need for amplifiers is for our pre-manufactured music. There we want the most accurate amplification, not the modifications made by a overdriven tube amp.
I don't read AC A human right
I'd also love to see a NES synth.
Then you might want to have a local computer engineer build a MIDI interface that plugs into an NES's cartridge slot. The people on the forums at nesdev may be able to help you.
But would you agree that if one runs a solid state amplifier within the portion of its response where it does not clip, it will reproduce the sound more faithfully than a tube amp of the same price?
> can you please enlighten me on how these facts support his statement that tube and solid state amps "have almost no comparison"
Those facts are not supposed to support his initial statement, that's why he used the word "but" in there. They weren't supposed to support it.
His initial statement is made out of experience, it seems, which most people who have used both solid-state & tube amps for a considerable amount of time will agree with. They have a different sound quality and the construction is very different -- hence, "no comparison."
> and that he'd "take a tube [over a solid state amp] anyday"?
I won't necessarily say one is flat-out better than the other, but opinion doesn't necessarily have to be backed up with a torrent of facts. That's why it's an opinion; a feeling. Otherwise, it would not have been necessary for him to point it out -- it would be a given.
Happened to me this morning. So, today's the day. What are you going to do?
Ce n'est pas un vrai mouvement de robot!
My Peavey 5150 has a preamp out jack on it, which brain-dead soundguys often want to use to plug me into the house. Then they can't figure out why it sounds shitty in the house and fantastic through my uber-cheap Behringer 4x12 cabinet. The reason is because the house isn't getting the coloration from the poweramp.
Also, there are two ways of getting gain from most modern guitar amps. 1. crank the preamp gain (thus adding distortion), set post gain to desired volume. 2. leave preamp low, crank postgain, thus cranking volume and adding distortion. Control distortion using volume knob on guitar. Way #2 sounds incredibly better, which is why guitar players are the bane of soundmen the world over, and also why there exist such products as the Marshall Powerbrake, which allow you to crank your tube amp, yet keep a reasonable volume going to the cabinet. Way #2 produces a more 'real' overdrive sound, as opposed to the pixillated, industrial kind of sound that you tend to get with low volume/cranked preamp.
The Marshall JCM would likely sound the same, or similiar, if the preamp stage remained the same, and a solid state poweramp were used
Marshall does make a line of amps which do just that, called the Valvestate series. I have to admit that they sound very much like all-tube Marshalls, except I think I've noticed that they have more of a tendancy for microphonic squeal rather than nice feedback at high volume than the all-tube amps. I can't help but think that it's because of the nature of solid state. I would venture to say that most guitar players who use Marshall-style amps would pay the extra money to not have microphonic squeal.
I think we're talking at cross-purposes here. I asserted, based on the information I've soaked up in the last couple of weeks of discussion, that auditory path neurons do not present phase information to the brain for frequencies above a few kilohertz.
You've replied with links to researchers who work in neural spike train coding. I saw references to Berger's work, but could not find the work itself. None of the titles suggested anything about auditory path neural coding, but not being able to read the papers I can't be sure of that. Liaw's work is available from the web, but in the few minutes I have I haven't been able to find any reference to auditory path coding there, either. There's a lot of work with the hippocampus, true; but I don't see the connection between the hippocampus and the encoding of phase information by the auditory neurons.
I have no intention of turning this into a discussion of neural coding, because quite frankly I only know enough to know that I don't know enough. I will ask the nice gentlemen and ladies who've given these presentations to point toward some of their references, and happily share them with you. Note, however, that these will be works dealing with the auditory path only, and probably with some clinical studies of phase comprehension in hearing tests.
I mentioned spike rate as a limiting factor because the work that was referenced in these presentations, and which I have yet to cite for you, showed the phase alignment of auditory path neural spikes with the incoming signal, at signal frequencies up to the maximum spike train frequency and occasionally a bit beyond. If the phase of the input signal is being encoded somehow into the spike train from the auditory neurons, then that coding process is not well understood - at least not by any of my sources.
Are you really telling me that you are aware of work that specifically shows the transmission of phase information, in the auditory path, at frequencies significantly higher than the maximum spiking rate?
Ce n'est pas un vrai mouvement de robot!
Bu'... these go up to Elven!
And you, madam, are very ugly. In the morning, I shall be sober.
Odd harmonics vs EVEN Harmonics !!!!
If you want to preserve even harmonics when overdriving a solid-state amplifier, just make the positive and negative halves of the waveshape different.
http://www.rane.com/pdf/old/pi14dat.pdf
In GOD we trust, all others we monitor.
The part of the work of Liaw and Berger i know is about neural network simulations, they build a synapse model more closely resembling 'natural' systems. The main point of his simualtions, was that every synapse has his own set of similar functions, information is coded in the temporal dimension, with feedback from the post synaptic level.
That kind of setup shows an exponential processing power, very small differences in temporal spike distribution have a large impact on subsequent behaviour. The firing rate is not critical, timming between signals is.
That was maybe two years ago... look on US patents for Liaw and Berger work, they build some very small systems (11 'neurons') able to detect the speaker (single word, many speakers), or the word (single speaker, many words) variying the setups.
Again, I am not pretending phase information transmission, just that small phase shifts can produce large effects on posterior signal processing. Others works also indicates that the temporal dimension plays a crucial role on biological neuronal processing. Never read about firing rate as a limiting factor for information transmission on neural systems.
What's in a sig?
Hi, welcome to the party. If you look about 5 levels up, you'll see someone asserting that skin effect is audible in audio cables. I point out that in the example he cites, the total power loss is 0.020 dB at 25 kHz. I contend that this is completely and totally, under any imaginable condition, inaudible by humans and thus irrelevant. So yes, I am ignoring it. I also pointed out that the phase shift described in his citation was about 50 ns at 25 kHz, again too short (not significant enough) to be audible under any conceivable conditions. I also pointed out that neuron firing rates in the auditory path are limited to a few kHz, and that those neuronal spikes are synchronous with the incoming audio signal up to some few kHz, which (and this is the point of contention) may limit the auditory system's ability to report phase to the brain to signals less than some few kHz. Consequently, a phase shift of 50 ns is totally indiscernable by the human auditory system.
I can show, as does the grandparent poster's citation, that the signal DOES arrive largely intact, with neither amplitude NOR phase significantly affected. In this case, when I say significantly, I mean "to a level which is in any way perceptible to the human auditory system".
In other words, skin effect in audio interconnects is totally irrelevant - either from a phase or amplitude point of view.
Ce n'est pas un vrai mouvement de robot!
Seems like good, important work. Also seems irrelevant to the discussion, as near as I can tell. My assertion (still unsupported with citations -sorry) is that the auditory system is incapable of detecting or encoding information about the phase of the incoming signal in the neural spike train. If nothing else, the mechanical resonance of the hair cells prevents them from detecting the incoming signal's phase.
... :-)
I'm not disagreeing AT ALL that the phase of the spike trains contains information, or that phase shifts IN THE SPIKE TRAIN are irrelevant. I'm talking about the ability of the cochlea and related neurons to detect and encode phase information for incoming audio signals above a few kHz; above the speech region, basically.
And, moreover, the whole discussion is irrelevant to whether a 50 ns phase shift in a speaker cable, at 25 kHz, is audible. That's my fault; I brought it up to demonstrate WHY such short phase differences are inaudible. But we've gotten off on a bit of a tangent
Ce n'est pas un vrai mouvement de robot!
What he did is what's known as "begging the question". He said "X is good because it's obviously the best!".
to whether a 50 ns phase shift in a speaker cable, at 25 kHz, is audible.
Maybe is not audible, but we cannot say is not detected on the neuronal level. :)
The main point for me is that we can hardly accept 'firing' or 'spike trains' as a symptom of information transmission, synchronization, amplitude, or simply delay can be information carriers.
What's in a sig?
Maybe is not audible, but we cannot say is not detected on the neuronal level. :)
I think we can safely say that it is not detected at the mechanical level. I haven't yet said that neurons are insensitive to temporal variations in the incoming spike train. I think 50 ns is smaller than can be resolved, but that's unsupported opinion, not fact. However, I strongly believe that the mechanical transducers in the cochlea are incapable of discerning a phase shift of 50 ns at 25 kHz. The hairs simply cannot resonate that quickly. However, I'm not an expert in audiophysiology, either. I could be wrong. But 50 ns is way fast, way fast.
Ce n'est pas un vrai mouvement de robot!
Sure, but biological systems are complex, they are not made of individual, isolated systems. In the case at hand, even if cochlea is unable to directly transmit those rates, I think we cannot say that a physical wave way above audible range has no effect on neural processing.
ie: Even if the hairs are unable to resonate at a given frecuency, his biologic structure is under the load of the wave, and that can affect his response, maybe not the rate, but say the decay slope, or any other internal funcion of the structure. As you already said, on higer frecuencies neurons keeps firing, not on ordered secuence, but they keeps doing his work.
Anyway, it seems we are in full 'hair splitting' no? :)
What's in a sig?
You don't need to implement a heuristic Cool Edit filter. Cool Edit already comes with a filter doing exactly as you described, and it's called Effects > Amplitude > Hard Limiting. It amplifies the whole mix while compressing the peaks that would otherwise saturate.
Not a flame to me. The linked article ought to convince (both of?) the Undecideds that most of current Subjectivism is merely part of a sad history of Fooled By Randomness. [1]
... Harmonic that is produced. And it mentions crossover distortion, a very audible problem on low signal levels, as well, for which I'm not aware of a standard measurement approach.
But it also shows that the most widely quoted measurements don't characterize sound as well as we'd like. Total Harmonic Distortion, for example, has very different effect on the listener when it's 2nd vs 3rd vs 4th
Also not mentioned, if there ARE pumping effects from a sudden surge of output temporarily drawing down the amp's supply voltage, shifting the amp into a different bias situation, you'd expect steady-state measurements to miss any result; simple impedance in the power circuits could cause something sorta like crossover distortion that could make lower-level signals sound odd. However, you won't hear me claim that amps require some exotic technology or else they're crap, since I don't have any measurements of this potential effect.
I'm reminded of Moneyball, wherein Batting Average, a widely-followed indicator of a hitter's skill, is replaced, very advantageously, by a formula that includes Walks and multiple-base hits. Gave a better indication of how well a player was contributing to Wins, versus Losses. (Yeah, baseball has that ultimate objectivity that Audio Engineering lacks, but you can still go into the bars and talk about "class," "style" or whatever.)
The article also cites Lysenko and (new to me) the sad story of Blondot, who worked himself into a frenzy about unmeasurable effects that regrettably didn't exist. But I think we ought to be open to previously-unconsidered ways that equipment is unfaithful to us; it's part of the scientific tradition that also produces Quantum Mechanics and superconducting, and that gave us gravity and the heliocentric view (even if it also gives us Cold Fusion for a while). As the Structure of Scientific Revolutions shows, even those with a high commitment to non-subjectivity have a hard time dealing with conflicting facts and opinions. Expertise needs to be supplemented with objective, large-sample tests. Those should put us on pretty solid ground, but are hard, and costly to do. They're also unnecessary when the purpose is to get a sound that helps convince you that your position on sound reproduction is correct, or to justify charging extra for a box that incorporates some cutting edge features.
I'm curious about the example of the cutting head. I kinda thought that Op Amps were intially developed to emulate the physical properties of such devices, and that it's pretty simple in both the domains of electronics and partial differential equations, to precompensate for the inertia... you'd send the appropriate magnitude of negative voltage when you wanted to put a hard limit on the positive inertia. But of course, even if you COULD perfectly flatten the top of a loud spike, it'd splatter the listener with all those nasty odd-order harmonics, and your listener would regret that you did so. Woudln't most listeners prefer some softer limiting that'd produce a lower distortion level? And don't current digital analyzers allow pre-leveling every little scrap of music so that no waveform actually needs be hacked up?
The article also mentioned how many tube designs produce lots of 2nd (1 octave) and other even harmonics that produce a "choral" or warm sound. I don't know exactly how producers/engineers cut the cake on this, but I'd mix for a pretty dry sound on vinyl, so the tube school didn't get soupy wet ringing, the SACD crowd got their ultra-crispiness, and yes, I'd probably compress the CD format because it'll most likely be heard in higher ambient-noise situations, where a constant loudness trumps the occasional squawk. I thought the DSotM reference was fascinating because it showed the engineers had apparently done just that: tried
"Inquiring Minds Want to Know!"
Yup!
Ce n'est pas un vrai mouvement de robot!
Well, you can't expect me to realize that you're the same guy each time if you post AC. Sorry. If you think I'm trying to avoid you becuase you 'got' me, you're completely mistaken.
.005 ohms or .006 ohms.
Now, I hadn't seen that you've clarified TWICE or more that you're referring to overall length of all conductors in the system. I saw something like that once, but I honestly didn't think you were serious. I mean, the skin effect gives us an effective increase in the effective impedance and self-inductance of the wire... but you're talking about the length of the wire in completely inductive structures. The overall phase shift and power loss in the signal due to voice coil inductance and winding capacitance is several orders of magnitude greater than the microscopic level due to skin effect. Same thing for transformers.
And exactly what difference in impedance are you referring to? It's not as if the voice coil of the speaker sees a 1 M source impedance or anything; ditto with the transformer secondary in a tube amplifier. The primary may see a source impedance of some kilohms, it's true. However, the previously-mentioned transformer inductance is several orders of magnitude higher than that caused by skin effect. It's rare indeed to find a tube output transformer which tests anywhere close to flat at 25 kHz, and that's not because of skin effect. It's because of the primary inductance. Tube output transformers need large primary inductances for good low frequency performance, but of course this starts to affect HF performance...
In fact, shouldn't operating in high-impedance circuits REDUCE the effects of skin effect? After all, power loss is proportional to I^2*R, and the higher impedance circuits you refer to operate at MUCH lower current levels. The wire impedance, with or without skin effect, is several orders of magnitude smaller than source or load impedances. They're called circuits intentionally, right? They go in a circle? Impedance in the circuit is the sum of the impedances around the circle. If you've got a source impedance of 1M, a load impedance of 1M, it doesn't matter whether the connecting wire's impedance is
Then you have the fact that internal interconnections are usually made with smaller wire, and so the ratio of skin depth to wire thickness is more favorable...
I mean, it's nice that people take this all into account, but the overall effect is actually worst in those speaker cables, and it's totally inaudible there. I'd be glad to see a derivation which refutes my statements in a rigorous way. I'd also like to redirect you to this link whih may be of some interest.
Ce n'est pas un vrai mouvement de robot!
How did you read that?
Ce n'est pas un vrai mouvement de robot!
And thank YOU, for a reasoned and only moderately impassioned discussion - on Slashdot, of all places!
Ce n'est pas un vrai mouvement de robot!
First off, you apparently assume that the only issue is sound reproduction when you speak of distortion not occuring under normal circumstances. And while it happens even there, the huge world of naturally-occuring distortion is guitar amplifiers.
And there are darned few SS amps that even get close to sounding like good tube amps. Distortion is the biggest area, but there are others, as well.
Does everyone like tube amps? No. Does everyone need a tube amp? No. Are they different? Yes. Are they better? That's up to the individual. But a huge number of individuals prefer tube guitar amps for overdriven sounds, even in blind tests.
I grew up on tubes. Like everyone else, I abandoned them in the 60s. Like a lot of other folks, I eventually realized that some of the sounds I wanted simply weren't there with solid state amps. Will they ever be? I have no idea. But they aren't today.