Slashdot Mirror
Cheap to Audiophile with Simple Hacks
petertrog writes "The IEEE has a story showing how you can turn a cheap DVD player into something that sounds a whole lot more exotic. All you need is a small budget, a soldering iron and a desire to void your warranty."
Build some cheap speakers to go along with the player http://members.aol.com/_ht_a/Debertin/spbuild.htm
"Simplify, simplify, simplify!" Thoreau
Nooo, you need MONSTER CABLES for the best quality! Aahhh, your signal!!
Nuts, from what I've heard.
Wow, an audiophile article from the IEEE. Next thing you know, we'll have witch doctors contributing to the Journal of the American Medical Association.
Strange things are afoot at the Circle-K.
All you need is a small budget, a soldering iron and a desire to void your warranty.
Small budget - After getting a new computer, I have that
A soldering iron - Oh yeah, I've got that
And a desire to void your warranty - My desire to void my warranty has never been greater...
I'd like to see him put this stuff on the scope before and after each of these changes. That way we could get an idea of what he means by a 'dramatic improvement'. I can see the op-amp changes and the power supply upgrades helping a lot... However I have a hard time believing that he would be able to demonstrate a difference in the analog output with some reference tones by, say, buffering the crystal from vibration on a standard scope. I'm sceptical he can hear the jitter too. Even cheap clocks these days are pretty damned good once everything warms up.
I dunno, my time is too valuable to bother doing the upgrade myself. Better just to buy the high-end at 10x the price and save 100x in the cost of my time.
Ruby Neural Evolution of Augmenting Topologies
That is the first real 'Audiophile' tweaks article I have ever seen. It actually detailed real changes you can make to improve the sound of your equipment.
The only reason people purchase expensive interconnects etc is because those components are very easy to change. NOT because they have a significant effect on the fidelity of reproduction.
To really improve the sound you have to improve power supply, decoupling caps etc, but even though the components are very cheap, it's a lot harder than buying a $500 interconnect cable.
I hope to see more articles like this in the future!
I grabbed one of those $35 "5.1 surround sound" speaker systems from Wal-Mart. They only accept a stereo input, and just kind of mix in the surrounds, center, and sub. So I popped it open and ran the numbers on the chips inside, locating the 6-channel volume control IC. I discovered that if I ran an audio signal directly to the inputs on the chip, it bypassed the stereo upmix. A few wires and drilled holes later, I had actual surround sound for my computer. Not gonna say it's the greatest sounding setup ever, but it was cheap.
This article is basically an advert for LC Audio (whose own stuff doesn't look anything special - look at the ringing on the scope trace of their wunderkind clock oscillator), mixed in with the usual audiophile crap (where's the blind A/B comparison?) with a healthy dose of stupidity; anyone advocating replacing safety-rated components on the mains side with unrated "audiophile" grade parts deserves to be sued by the first idiot who burns his house to the ground. The mains is a hostile environment, those components are designed to fail open-circuit for a REASON!
Jon.
Man, this is racy stuff. When I read the first line:
When those of us who are into "gadget porn" look at the latest state-of-the-art home entertainment gear
I didn't know what he was talking about until I got a little further:
Taking the modification yet further, you can also replace both of the X-rated capacitors
...now I know the purpose of my EE degree.
It seems simple enough. Basically you're replacing components with ones that are better with no major rewiring of the circuitry. Diodes with faster switching times, add noise reducing capacitors, gold terminals instead of nickel or tin, replace the op-amps to get better slew rates and less distortion... etc. All this is pretty much what the more expensive models would have done anyway.
This is a good general reference for those who aren't afraid of electronics. But, I strongly warn against it for anyone who really doesn't know what they're doing (especially the ones who can't solder). These components are simple enough, and swapping identical devices shouldn't be too hard, but going from schematic to PCB is very challenging if you're not used to it.
On a side note... Favorite quote: "Plug it in and turn it on. No sparks or smoke? Terrific!"
...Gaurenteed oxygen free, is the only material to make speaker wires from; unless youre really high end, and buy the solid gold, 4AWG, rope lay, speaker wires. ...And if you have that kind of discerning ear, and money to back it, have I got a system to sell you... ..and some really good swamp, I mean, lakefront property to sell...
Truth isn't Truth - Guliani
The real reasons for recording with greater resolution (bit depths and sample rate) than your target media are :
To allow more headroom while recording.
To prevent generation loss while editing and mixing.
To enable releases on newer media than CD. (Or just upsample the 44.1, no one complains anyway.)
Sure, 24/96 does sound a little better than 16/44.1 on a solo'd vocal, but once you have your final master, all compressed and eq'd up, it makes very little difference. There is only around 6db dynamic range on modern releases, and the majority of playback equipment does very little above 18k anyway, so even 16/44 is overkill for domestic systems.
My $35 DVD player has a digital (coaxial) output, and my PS2 has an digital (optical) output (but, the laser is blown and it can't play disks with even the smallest scratches). Why mess with the electronics inside when you can get the audio data right off the disk into your system?
autopr0n is like, down and stuff.
High end audiophiles will squak. Meridian's G98 costs $6k (review), the Lexicon RT20 is $5k, an Ayre costs $6k, and the Arcam FMJ 29 (highly rated starting end of high end) will set you back $3k. The top reference player, Meridan 808, will set you back $20k.
The Denon 2910 (about $600) (review) is the beginning of better quality players. The article being discussed does exactly what a lot of the higher end players do -- swap out cheap parts for better ones. For those who don't think it makes a difference, you've never had the pleasure of good quality sound. A wide, three dimensional sound stage with clear separation of instruments and fine detail puts a smile on your face. Being able to get that for much less than above (and have the second pleasure of do it yourself) is well worth it.
.. Of electronics I buy; the main amp in my car I bought for ~$150, put in ~$50 in better transistors, and a few critical resistors, and have a really nice amp, until it overheats. The watercooling project is next, I guess.
The thing in the article that pegged my bullshit detector is the 'audible difference' in capacitors. I design high frequency pulse amplifiers, and at subnanosecond risetimes, capacitors act pretty awful. but in the audio range, there is no way to hear the difference in a good quality capacitor. Below 1MHz there isn't enough difference to measure. You might hear the difference between a low quality, floor swwepings quality z5u capacitor at 20kHz, an a high quality silver mica cap, but I seriously doubt it.
P-channel mosfets are more expensive than N channel mosfets; If you look at the parts in any car amp, the P-channel parts are the lowest rated; replacing them is an easy way to improve the capabilities of an amp. but you have to upgrade the power supply as well, usually to take advantage of the improvement.
And replacing the resistors in the signal path with metal film, if they're not already, is an audible improvement.
Replacing the capacitors, with no design check, will result in shit blowing up, just as specified. Inrush current is a bitch. Replacing the output caps on a power supply board with larger ones is not a good idea; the lead inductance is a design constraint. The need to go in the same holes.
Also, FRED diodes are soft recovery, with no ringing. Schottky diodes ring like a bitch, and are why fred's were developed.
If you add capacitance to a switching power supply, do it at the circuit you want to help out, not at the power supply. The resistance of the wire going to the circuit board will damp the inrush current to the additional capacitance.
1 ohm of wire makes a huge difference in the surge current when you turn it on.
If I spent $10 on a capacitor, I guess I'd say I could hear it too...
Truth isn't Truth - Guliani
Well, maybe if your dog is an audiophile, but as a human I'm perfectly satisfied with equipment that reproduces sound in the frequency range I can hear.
English is easier said than done.
A signal which comes out cleaner on the scope, up to a certain point, will also sound better to the human hear, but past that point, it just comes down to preference. This is why studio engineers often add "color" to a song, and why some audiophiles still swear by vaccum tubes. The vaccum tubes don't produce anywhere near a flat frequency response through the 20kHz range, but instead color it in a way that people describe as "warm."
The point is, you can try and make changes to flatten the frequency response as much as possible, but it may NOT be the sound output you're looking for. The scope would, of course, be useful to track down problems with power supply noise, but when it comes down to swapping op-amps or other stuff, it's often times more subjective than not, which is what his article says. Here, seeing the scope output is useless, because the only important this is whether you like the resulting sound output.
I'd like to agree with you on the part about the clock though, but I have never looked clock outputs when they get shaken/etc, so can't really comment.
But can he tell me how to build a filter to add distortion so it sounds like the "sweet, sweet" sound of a $20,000 tube amplifier?
Sometimes it's best to just let stupid people be stupid.
Don't most people hook their DVD players up to their receivers using either an optical or a coaxial digital cable? Why would changing anything in the dvd player make any kind of difference in the sound quality if all the player is doing is passing along a digital bitstream to the receiver?
These are the sorts of things that get you from 16-bit performance, which is pretty easy, to 24-bit performance, which is dreadfully hard. Even air currents blowing across the leads of your opamp will cost you an LSB or two.
Wrong. The clock is in the player, transmitted over S/PDIF, and recovered by the DAC. That transmission and recovery step is fraught with peril, and it is guaranteed by the design of the S/PDIF signalling to have data-correlated time domain distortion. The only way to avoid this problem is to put the master clock in the DAC (as you say) and slave the player's clock to it, so that the two run in synchronized clock domains. But only DIYers and professionals have such equipment. To the best of my knowledge no manufacturer has marketed a consumer DVD player with a clock-sync input.
Audiophiles believe in paranormal phenomena that cannot be verified by any scientific process.
So this guy's player sounded better after he replaced the caps, resistors, power supply? He could tell by listening to it? With how much - a day - interval between the two auditions?
One of two things happened - he made no discernible difference and only imagines he improved the equipment. Or he made it much, much worse, and likes the distortions he introduced.
Correctly functioning players - even the cheapest - have such low noise, low distortion, and flat frequency response within the human audio spectrum that nobody has yet been able to demonstrate - in double-blind level-matched synchronized A/B comparisons - that they can tell the difference.
If you want to improve your stereo performance, concentrate on the "I/O" devices - speakers, monitors, and microphones. They introduce many orders of magnitude more color than the electronic components.
How about learning a wee bit about how these things work, first?
1) For something as subjective as viewing paintings and sculpture, I find it interesting that everyone here is trying to bash people for trying to increase the quality of sound in their stereo. One reason may just be a generational problem where modifications were much more apparent in equipment 30-50 years ago. 2) I also find it funny that everyone is bashing the audiophiles when only a few stories below is about a guy who memorized >80k digits of PI (far less useful than modifiying stereo gear). Just so you know how relevant 80k digits of pi is: "If one were to find the circumference of a circle the size of the known universe, requiring that the circumference be accurate to within the radius of one proton only 39 decimal places of Pi would be necessary."
http://www.brentcastle.com
In the end, get another brand-new player and someone to help you double-blind test it. And please, broadcast it live on the net.
This is not an engineering hack, this is the same trap all the tweako audio magazines fall into. Sure it sounds better after he spend a hundred bucks and a few hours of his time... show me the measurements and I'll believe it wasn't an emotionally influenced subjective improvement.
The starting premise, that manufacturers use the least expensive components they can get away with is no big news. This has been considered good engineering just about forever: use those parts that are good enough technically and least costly. The key is "good enough", though for what? The subsequent discussion on audio and video quality just indicates that the player is working as it should. As to distortion, there is only the subjective opinion that the cymbals don't sound as clear as they should, but there is no further indication of whether this comes from the player or the amplifier chain following.
Then the discussion proceeds to take apart and redo the power supply... Not components in the signal path, but the power supply. A switching power supply that is powered direct from the mains, with X and/or Y-rated capacitors and inductors in the power entrance, and a somewhat carefully orchestrated feedback loop that causes its components to oscillate and generate the correct DC voltages for the electronics. Apparently, (and fortunately) most of the really important components are surface-mount and thus not amenable to this kind of tinkering. The argument goes on that this more "stiff" power is needed for more accurate bass-response. Hello? this isn't a 30 Watt tube-amplifier we are talking about here, where such an argument might hold, but something that puts out a few tens of milliwatts of power into maybe 600 Ohms at the most. Unless the power supply is pathologically feeble, this is really just -- marketing-speak, to use a polite term.
However, even if putting in larger filter electrolytic capacitors might be harmless, the replacement of the X-rated capacitor with an "Auricap" which is evidently NOT X-rated, sounds dodgy, as in potential fire hazard. The Auricaps seem to be marketed as non-electrolytic replacements for electrolytic capacitors in the signal path, and might do a fine job here, but we're not expecting any of our precious signal to enter the mains are we?
The fact that there is an X-rated capacitor there at all and not just a cheaper one, is that this is sitting across the mains voltage, and has to conform to specific requirements from the UL, CSA, TUV and so on, lest they refuse to List or certify the equipment for sale. And probably more important, that the component fails safe and does not start a fire.
Googling for "aurocaps" shows several sites catering to the same merry lot who depends on "oxygen-free" cables, and praise the virtues of the gold-plated RCA connectors... There is a reason why professional kit uses XLR or BNC connectors, or even 1/4inch jacks by the way, and it has to do with mechanical and electrical stability and shielding, not any magic properties of gold or nickel that makes one good and the other bad.
It goes on about replacing more of the bypass capacitors in the digital processing section, and mentions the possibility of clock jitter. Technically correct. But no quantitative information, no measurements done on a distortion analyzer or even a picture of the signal on an oscilloscope. Just all this non-scientific hand-waving that if we put in more expensive capacitors the sound will be better.
Finally, op-amps and possible replacements. Again, the observation is that the amplifiers are low cost, and obviously we could put in better and more expensive ones. Low cost is not the same as crummy; had the manufacturer put in really bad ones, everyone would have heard. Again, it is a matter of good enough, though the only parameter that might make a difference would be the noise of the amplifier. Unless they are really atrocious (with obvious effects on sales), gain and slew-rate would not matter, except for marketing purposes.
My guess for what might constitute the perceived "improvement" in this case, is that the frequency response of the audio chain has changed, boosting the higher frequencies, and thus made the modified unit appear to sound better.
SIGBUS @ NO-07.308
Higher frequency response isn't the reason to go to 192kHz.
If you think you can really hear past ~22kHz, and if your speakers went there, and if your cable could pass that frequency, well, so be it, but you're hearing what isn't intended to be heard, dog.
The reason to use higher sampling rates is to obtain more accuracy in that critical 20Hz to 20kHz range.
Consider how many samples a 10kHz sine wave receives, if the sample rate is 40kHz. Yup, 4 samples. So you have four digital 'dots' which get connected together to form the same waveform on the analogue side. Not going to happen.
PCM audio is inherently flawed in that as frequency increases, resolution decreases.
In general, sounds in that higher-frequency register require more accuracy anyway.
You're right of course, it all gets thrown on a 44.1/16 CD, and then the kids put lossy compression on it, and the radio station compresses the mix to the last 4dB.
Consider this though, if we ditched PCM for something better, would anyone really sell any more CD's?
...wasn't TFA itself but its link to the Troubleshooting and Repair of Small Household Appliances and Power Tools FAQ. Good stuff there.
"I came here to kick ass and chew bubblegum. I'm all out of bubblegum." MSE USC APX AIA CSI CASp
Screwing around with the power supply is just stupid, a decent Tripp-lite conditioner or a UPS would handle line noise much better, simpler, and more safely..
Replacing the op-amps with better ones is probably the best tip in the whole article, and the only thing that is likely to have a serious impact on the sound. Replacing caps and other components in the signal path will have some effect.
The jacks have to be the dumbest thing I have ever heard.
All this 'gold-plated, super oxy-free' stuff is pure hokum. Sure, the cables might conceivably make a difference when you're using an Apogee converter to run audio from your RME Hammerfall through your $50K amp to your $250K mastering monitors.
But on a consumer-level system with unbalanced jacks? Please.
Unbalanced cable can only be run for 3 feet without serious risk of RFI and EMI corrupting the signal. You can run balanced cable 1000 feet before you face similar risks.
Pro recording and audio environments use almost entirely balnced gear, because it provides the signal quality necessary for major recording projects. For cable, it's plain old Mogami or Belkin. We break out the fancy-looking gold-braided super cable when we get a cranky performer who insists that our gear is simply not capturing his muse, because he always delivers perfect performances. Slap those into the mic chain, and watch them listen to the playbacks, nod knowingly, and say "Yeah...it sounds right now"
Nothing has acutally changed, but it sure makes some people feel better, and the same thing is at work in the audiophile arena.
Sure, different compositions of metals have different abilities to conduct signal, but once you get to a certain level of qaulity (which all basic cables meet), it doesn't matter too much.
"Why don't you interface with my ass...by biting it!" -Bender B. Rodriguez
Spoken like a first-year undergraduate! Search the literature for microphonic ceramic. The microphonic effect of multilayer chip capacitors is very well known.
when the warranty expires for a gadget, an average joe would be like, "shoot, i need to be more careful now". when the warranty expires for a gadget, a geek would be like, "sweet! i get to take it apart now!"
HD Trailers
For God's sake there are children reading - must we discuss audiophillia on slashdot??
So wait, you're going to replace a toslink cable with a coat hanger?
...
You're going to replace a toslink.... fiber optic... cable, with a.. coat hanger?
*head explodes*
audiophile, n: Someone who listens to the equipment instead of the music.
while (!asleep()) sheep++
Rip EVERY single last wire out and replace with silver wire (or, if you can't find that, then use silver coated oxygen free wire), replace all of the capacitors with polypropylene, silver mica, or paper caps (use only 10% or lower tolerance caps). Replace all resistors with 1% tolerance, zero capacitance mil-spec pieces (they cost a dime each at most electronic surplus stores).
What you just bought for $125 or so on E-Bay, along with $30-$40 in parts, with a few hours of soldering work will give a MacIntosh amp a run for the money.
See if you can find the pentode-triode modification online or in a VERY old "Glass-Tube Audio" magazine and convert the first stage tubes to triode operation instead of Pentode, and it will DEFINATELY keep pace with amps selling for up to $2,500 or so. (my modded amp's power output is essentially flat from 15hz -> 80Khz with only a 3db rolloff at 100Khz)
If you are a dyed in the wool audiophile who likes the "vintage" look, then you might want to consider a project like this.
It's a lot of fun for only a couple of hundred bucks, and it will sound like it's worth thousands.
yeah, but if you lower the ESR too much, then that leads to leakage of weird, malformed RMS spikes at high current.
... and then they built the supercollider.
"ascetics can be important"
Thats bloody inhumane..making speakers out of monks.
Ascetic:A person who renounces material comforts and leads a life of austere self-discipline, especially as an act of religious devotion.
I think the word you were looking for was Aesthetics
Next time just use "looks" maybe?
Here, seeing the scope output is useless, because the only important this is whether you like the resulting sound output.
The scope isn't just to ensure a flat response. It can also tell you if changing one capacitor, op-amp, etc. for another one had any effect at all, or if the difference is psychological.
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
- Making the power supply filter capacitors "20% bigger" is a silly idea, for MANY reasons:
- Most electrolytics come with a -20% to +100% tolerance. Because of their construction, it's hard for the manufacturers to get them much closer than that.
- Plus in any well-designed power supply the capacitors are intentionally chosen a bit oversize to handle 50Hz or low line voltage situations.
- Electrolytics have a steep cap versus temperature curve. The engineers know this and specify 40% bigger caps to handle the times you use your CD player in Alaska.
- The filter caps are isolated from the audio circuits by a voltahge regulator chip, which provides about 60 to 90 db of isolation. There's just NO WAY one can notice the effects of a 20% change in capacitance, when the effects are mulffled by a factor of a million to a billion.
- The original filter caps have to be very specially chosen for compatibility with the high frequencies and ripple currents. Is it likely the average joe tweaker is going to choose something that approaches what the actual power supply designer chose? Not likely.
- Replacing the power supply diodes with "faster" ones is a waste of time and money. Any noise the old diodes generate (if any) is many decades above thre audio range. Plus the CD player has to pass FCC emission limits, so they can't be too noisy to begin with. Skip this mod.
- Changing op-amps is really ridiculous. Op amps are always used with huge amounts of negative feedback, which reduces their individual quirks and distortion by a huge factor. I've worked with dozens of op-amps, and have never found one that's not capable of handling your typical audio. A typical 30 cent op-amp already has about 0.001% distortion, thousands of times lower than a golden-eared indivuidual can discern. Skip this step too.
- Tapping into the DAC outputs is a REALLY bad idea. Apparently this guy hasnt a clue about Nyquist limits and sampling rates. You HAVE to filter the output of the DAC's, as they're intrinsically rife with sampling-rate related harmonics and aliasing. Those op-amps are there for a reason!. Don't even think of doing this.
- Putting caulking on the crystal is wet-your-pants funny! There's absolutely no need for this. Crystals are designed to resonate at one frequency. They're totally insensitive, by factos of a billion or more, to any other vibrationary frequency. As an example, there are very precise aerospace radios, with dozens of crystals, none of them caulk-damped, used for life-critical navigation and landing systems, and they work just fine for decades of constant use in vibraty, shaky old prop planes. Put the rope caulk around your windows, not on your crystals.
- If you like the look of gold-plated jacks, install them. There will be absolutely no discernible difference in the sound, but they look neater.
Sorry to rain onthis guys parade, but IMHO there should be at least a token nod towards reality.