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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.
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.
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)
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.
this would get an "obvious" tag.
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.
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.
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.
"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
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-
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.
h**p://club.aopen.com.tw/News/News_showAnswer_Old
and.. site with some comments.
h**p://techreport.com/news_reply.x/3670
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
Or, you could just not purchase music that sounds like crap...
Patient: Doc, it hurts when I do this.
Doctor: Don't do that.
Or, maybe you could get a really tiny tube amp, and listen at normal volumes, and hope that all the "pleasant" distortion of the tube amp in overdrive cancels out the overmodulated recording.
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.
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
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.
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
Processing signals at a resolution of 24 bits (maybe even floating point calculations, 32 bit, 64 bit???) combined with billions of operations per second can probably simulate whatever positive effects that vacuum tubes provided. The trick would be trying to figure out what those qualities are and developing efficient algorithms to implement them. The main benefit? It would be low power, easy to reprogram, and it won't change with time, temperature, or RF interferrence.
Of course, this doesn't make the analog components any less imporant. Once you get out of the realm of digital signals, there is still a great need for efficient analog circuitry. It's just how much of this circuitry you need to focus on can be reduced by using DSP.
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.
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.
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!"
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!
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.
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.
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
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.
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!
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!
http://www.rane.com/pdf/old/pi14dat.pdf
In GOD we trust, all others we monitor.