Best USB cable to use between computer and dac?

[Julf]

Oh yes, plenty of snake oil everywhere. But I guess I must disagree with your point about wine, coffee, chocolate and food - yes, ultimately enjoyment of them is truly subjective. But even then I am interested in things like sulfite, alcohol or sugar content, not to mention additives. If I can't taste the artificial additives, do I need to care they are there? Sure enough.

 

And in audio, we are talking about things that are less subjective. Enjoyment of music is definitely subjective, but we are not discussing music here, we are discussing complex technical systems used to reproduce the music. And while our ears are an important instrument to judge the system, they are definitely not our only tools, or, if you want to improve your system, not necessarily the best tools.

 

 

 

[Mark Powell]

From a UK scientific magazine, in an article about additives -

 

"Regular Coke, take out dental insurance. Diet Coke, take out life insurance"

 

Sorry!

 

[Jud]

And while our ears are an important instrument to judge the system, they are definitely not our only tools, or, if you want to improve your system, not necessarily the best tools.

 

A *very* interesting subject because there are a variety of ways to approach it. On the one hand, since music is something we listen to for enjoyment using our ears, then if our ears enjoy our systems more after some change, it is certainly an improvement, yes? On the other hand, even the most careful subjective listening doesn't have quite the same repeatability and ability to finely quantify changes that measuring instruments have.

 

As with many things, I'd choose a balance - a basis in measurable quality, while according due respect to the evidence of our ears. After all, I'm old enough to remember when the early digital (CD) playback systems measured fantastically in all the things that were thought of as significant coming from the vinyl era (no wow, flutter or rumble to speak of, virtually no surface noise, terrific potential dynamic range, near-perfect potential frequency response...), but many of us found our ears didn't like them so well. There was a lot of scoffing from objectivists who said we were all just imagining things, until we began to hear from the engineers and even marketing departments about jitter, and lo and behold, now it's an important measurable.

 

[barrows]

On Cryo treating. Mark, you understand heat treating of metal bolts for your airplane... You probably know that it is not uncommon for critical race car engine parts to be cryo treated, right? So I am going to assume that you also realize that cryo treating can/will alter the sructure of a material, right? Now, is it not perfectly reasonable to assume that be cryo treating a metal conductor, the conductor's structural properties are changed? If the structural properties are changed, then, it is also quite reasonable to assume that the new structure could change the way a waveform propogates along and through that structure, right?

 

I read (am not a gamer myself) that it is quite common for high level computer gaming enthusiasts to use cryo treated mother boards in their tricked out machines. Apparently they also MEASURE improved performance from doing so. I cannot say that cryo treating a MoBo is going to improve a server for music, but certainly, considering the evidence, I would not discount that this is possible.

 

I have experienced cryo treating fuses making a difference. When I was with PS Audio we distributed an audiophile fuse from Germany. This was a pet project of mine at PS, encouraged by our German distributor. I decided we should try cryo treating the fuses to add value (for fuses, cryo teating is really affordable, as the cryo lab charged by the pound, except for very bulky items, like saxophones; yes they actually cryoed instruments for many musicians). We tested the fuses, and the cryo fuse was a little better... from then on we had all the fuses cryo treated.

 

Here in the US is not hard to find a cryo service. I encourage anyone interested to try it with some cables (but mkae sure that they are not already cryoed by the manufacturer). It is not expensive to try.

 

"Personally, I fail to understand why this is a debate at all. It's really just a bunch of wildly different personal observations that people want to argue over. Kind of like an old Monty Python sketch."

 

Thanks CG, lol!

 

 

 

[Julf]

We are in full agreement here - as I keep saying, I am not ruling out that there are things related to the performance of USB cables we haven't figured out how to measure yet. So my attitude is "I am naturally skeptic, but if there is something, let's work together to figure out how to measure it, so that we can improve our cables (or at least figure out which ones are the best ones for a given price level)". But I am also hoping people who do hear the difference do help, by conducting true blind tests. I would also be very interested in hearing from someone who can (in a blind test) hear differences in cables when using simple, static tones as a test sound.

 

 

I have to note that despite what the marketing people claimed at the time, the engineers who designed the original CD system were painfully aware of the fact that it was a compromise - in terms of the 16 bit word length, but especially the 44 kHz sample rate, the error correction system and the lack of buffering. And jitter was instantly measurable - if not in the sophisticated way we do now, but as intermodulation products.

 

Too bad I don't have access to a proper lab anymore... Will see if I can borrow a decent spectrum analyzer.

 

 

[CG]

"we are discussing complex technical systems used to reproduce the music"

 

Well, yeah, but...

 

Most recordings are dreadful. Barry Diament, who really does know about such things, has posted just that recently here on CA along with his reasons why. So, what you (and everybody else) are asking an audio system to do is to create a plausible reproduction of the original in a form that your brain can imagine what the original might be like, even despite a crummy transcription. That you have almost no control over, by the way. Having a technically perfect reproduction system may indeed be counterproductive to achieving what you're trying to achieve. Over half the technically complex system has already done what it will do before you ever start.

 

In that sense, it is no different than a photograph.

 

So, as long as it doesn't rot your teeth or your brain, all seems fair to me.

 

[Mark Powell]

I don't doubt that cryo treating might make a difference, though I don't have any cryo treated parts myself.

 

It's just that the effect of dropping a complete laptop into a 77K flask of liquid nitrogen makes me think it won't work when you take it out. But they probably don't do that!

 

But even the idea of doing it on an unpopulated pc board worries me. With the different expansion rates of glass/epoxy and the metal tracks. Let alone a populated board, the plastic encapsulation of a typical IC, the gold or aluminium hair fine wires inside, and their 'eutectic bonding' to the chip, any wirewound ceramic resistors, electrolytics, etc.

 

And have you seen what low temperature (let alone 77K) does to solder? Our modern EU approved 'safe' solder, now the only sort available for other than aircraft and military purposes, is even worse, it crumbles at about -30 degrees C, maybe a little lower.

 

Regards

 

[CG]

Cryo treating usually has been used to change the mechanical characteristics of a metal. This usually results in the material changing at a molecular level, like in the case of treated steel, or by some residual stress in the material being worked out, as in the case of brass in a trumpet.

 

Fuses are constantly being thermally stressed - duh - so you can imagine why cryo treatment might make a difference in their performance.

 

For other electronic components, it's not as obvious. I'm not sure anybody has really done an investigation of how and why cryo treatment works for electronics. Anybody know of any studies that are easily accessed?

 

This has really fallen off the USB cable track. I apologize and will stop commenting on this thread.

 

[Julf]

Ouch, yes. You are absolutely right. And that is why it sometimes amuses me to read fights about the best cable - when the original signal has traveled through a huge amount of studio cables, not selected for their audiophile qualities. And then been compressed to death at the mixing and mastering desks...

 

[barrows]

"Ouch, yes. You are absolutely right. And that is why it sometimes amuses me to read fights about the best cable - when the original signal has traveled through a huge amount of studio cables, not selected for their audiophile qualities. And then been compressed to death at the mixing and mastering desks..."

 

I guess then, that by this logic, you do not care at all about the quality of your playback system?

 

Certainly, we can do very little (try and find the best version) about the recording chain-that does not mean we do not want to put together the best system for getting the most out of (often flawed) recordings. Considering that cables are lossy, and losses are addititve throughout the recording and playback chain; I want my system to introduce the least losses possible. I cannot change the cables used for the recording, but I can choose to use the cables that introduce the least additional losses possible in playback.

 

[REShaman]

Ah, a breeze of clarity just blew in. Thank you Barrows. No offense meant to others.

Best,

Richard

 

[Jud]

I would also be very interested in hearing from someone who can (in a blind test) hear differences in cables when using simple, static tones as a test sound.

 

I'm quite interested in the psychology of audio testing. It would not surprise me at all if the ability to differentiate among cables using static tones was worse than the ability to differentiate them using music (particularly with sparing production and vocals highlighted); which in turn would be worse than the ability to differentiate if the test questions were geared to whether one musical sample was preferred to another vs. identifying whether one cable or another was playing; which in turn might be far worse than the ability to differentiate using a recording or even a live mike feed of a loved one's voice.

 

I think you see where I'm headed, so I won't say much more other than the test atmosphere would seem to me to be a quite important and relatively unexplored area.

 

[Julf]

Jud,

 

You are absolutely right about the tests - and I think you are right about how the different tests would come out. But I am sure you can also see why I would like to find out if the differences can be heard even with a steady tone (implying no dynamic intermodulations in action).

 

[CG]

Sorry to interrupt the thread yet again; just want to address Barrows comment.

 

My point is that having a technically perfect playback system - whatever the heck that means - may not may not be the goal here. We are trying to create an illusion based almost exclusively on bad source material. Colored microphones placed and used badly, dubious mixing, and so on already perturb the process. Probably very badly. That's not even thinking about (important) details like cables and crappy opamps. (Before anybody starts - I'm talking about cheap and crappy opamps; better opamps really do exist.) Accurately reproducing that flawed picture may not lead to a plausible illusion of the original event.

 

Want proof for yourself? Beg, borrow, or buy (don't steal) a simple recorder and microphones. Make a few test recordings of music or even the noises in your back yard. Then listen to how they compare to the original event. I bet that even with a cheap recorder what you hear on playback will be better than most all commercial recordings. Not all, of course - there are some really great recordings available commercially and even for free on download. Almost all of these use techniques like Barry Diament describes on his web page. Even the guys who record frogs out in the woods and the guys who record ten minutes in the subway station produce more plausible recordings than most commercial offerings.

 

Personally, I want to be fooled into imagining than I'm listening to a recreation of a musical event when I sit down for a listen. Or, that I'm hearing about what the original sound guys heard when they made the movie sound track. I don't want to hear everybody's bad recording ideas along the way.

 

But, this all just me and my silly opinions.

 

 

 

[REShaman]

"Personally, I want to be fooled into imagining than I'm listening to a recreation of a musical event when I sit down for a listen. Or, that I'm hearing about what the original sound guys heard when they made the movie sound track. I don't want to hear everybody's bad recording ideas along the way.

 

But, this all just me and my silly opinions."

 

If I may add to your silly opinion(s),CG, based on those words, make room for one more where you're sitting (or standing).

 

In addition: The sentiments offered by Barrows, as well IMO, address, at least for me who is the only one authorized to represent me, is a worthy and essential perspective that does not conflict with but converges on the path to the ultimate outcome we pay tidy sums to attain.

 

I realize I left the heavy lifting to others,

Richard

 

[tarquineous]

There has been work done in this area and a few products offered. The ones I am familiar with are Triphasors, qol Signal Completion Stage, and TDS.

TDS made an active one and more expensive passive one with transformers. The active one sounded terrible, and the passive one very good. No longer in business.

The Signal Completion Stage is one we will be hearing more about. Richard Vandersteen uses one in his home system, and mentioned it during his LAOCAS speech, to members of the Society. This one is expensive for most people (about 4K), but is well regarded for its sonics.

 

These are the subject of another topic, but each devise is still subject to sonic variations due to cables and recording venue.

 

[steve2701]

That all was.

I admit to not having read any of it before as I inevitably find 'cable wars' to turn into circular arguments very quickly, then decline into ever deeper ways of cynically calling each other names.

But then I'm English, reading a lot of British forums, (hmm English, British - does it matter?)

this entire thread has actually kept well within the bounds of decent debate for the most part, which is very refreshing.

I would like to ask a couple of questions if I may, I'm no scientist, but love physics and chemistry, I am aware of what should happen, but then I'm also happy to admit that my ears are trusted by my brain as well.

Now what would happen if BOTH sides were actually scientifically correct?

No, I'm not bonkers, this is a serious question.

Someone has already mentioned that the laws of physics cannot be broken, and I 100% agree with this, but it has also been said that we do not know all there is to know, and I am also certain of that.

So a set of purely scientific and repeatable tests prove that cables X, Y, & Z do exactly as they were expected to and the results were exactly as expected they would be under test conditions.

Then, while not being tested, a completely different set of results were obtained, and for these results there is no possible know explanation (at this current time).

A conundrum then exists - which to believe?

They cannot both be correct? Or can they?

Which side of the reality fence do you want to sit on?

It has also been said here that there is stuff going on that we do not understand / know how to test.

Now if I said the above experiment can be done,(or one very similar to it) and repeated, in a school lab, and the results were always the same every time (ie - two sets of different results) what would it prove and say of human nature?

Can we accept that not everything acts as it should do all of the time - or do they have a secret life all of their own?

Barrows said something that sparked this memory in my head from some old science stuff we did at school with electrons / particles and was also recently on the TV.

My apologies for the length of post, but would honestly like to read your thoughts on the above.

Could it ever be acceptable to the many that both can actually be correct?

 

[CG]

The measurements usually discussed with regard to anything digital aways has to do with the accuracy of the bits. In this case, I don't believe anybody questions whether the bits are un-corrupted.

 

The second measurement usually talked about in digital system terms, not just here in audio land but elsewhere, is jitter. That is time corruption of the bits themselves. In many applications, this doesn't matter. But at least in the case here, the bits are converted back into analog signals by the DAC. If the DAC gets its conversion clock from the incoming bitstream, then any conversion will be distorted to some degree by the modulation of the clock.

 

In the case of a perfect asynchronous USB fed DAC, the incoming data is not used to create the DAC conversion clock. In theory, the conversion is as good as the quality of the DAC's internal clock.

 

But, we don't seem to have too many perfect DACs available at a price we want to pay. So, for example, any noise that also rides on the USB cable connection also might find its way into the conversion process. This could take many forms, but the general idea is that fidelity will likely be compromised. You can measure this and show it mathematically.

 

Even if the DAC itself is perfect and completely immune to computer generated noise, we still have the problem of a really electrically noisy computer of some kind being connected to sensitive analog circuitry in the preamp, the power amplifier, and whatever else is in the system. In this case, the noise may reach the preamp or amplifier through the DAC itself. The DAC may just be an innocent carrier. Or, the computer noise might travel through the AC mains connection to the preamp or amplifier.

 

The characteristics of the USB cable can have a big effect on any noise transmission. Various people who have access to the right test equipment and the skills needed have measured this. (This is not unique to the digital audio world.) I suspect that the people in the audio biz who have made these measurements wish to keep the information to themselves, for a variety of reasons. Not the least is that noise by itself does not tell the whole story. Amateurs who have made measurements tend to get blown off in the public eye, even if they may be esteemed professionals in similar non-audio engineering careers.

 

In summary, having perfect bit transmission is a necessary but insufficient condition for best fidelity.

 

Here is an article that was published long before anybody was thinking about using a USB connection to a DAC for high performance audio in the home. It's about analog interconnects, but his point is that there is more than meets the untrained eye.

 

http://www.soundstage.com/articles/pete01.htm

 

Now whether you can ever get anybody to agree with anything is another matter altogether. Personally, I'd settle for all the name calling anybody wanted if there could be some progress. I hate to think how many people take a look at CA for some useful information and run away because of the discourse.

 

[JDFlood]

Music it a very complex sequence of different sounds. Let's say instrument sounds. Each has individual starts and endings, like drum beats. The rise and fall of volume as the expand and contract across the spectrum and harmonics. Then there is the relationship of each beat to each other and the other sounds. Very quickly you realize you are not listening to a single varaible but dozens. So for your mind to "focus on" a specific instrument sound is a difficult thing because, first it is instantely changing over time, waxing and waning before you do you are able to completely characterize it in your own mind. Equipment changes can be easy if the change is large and to a single facet of the sound, like bass more pronounced, but usually by the time we get to cables we are speaking of more subtile but very important changes. This is why tracks like Spanish Rose by Rebecca Pidgeon is so useful in evaluating equipment is there are single instruments that vary slowly over time. Rebecca's voice can be narrow and distant or full bodied and up front where the system has mid-range bloom. It is a really good test recording.

 

Hearing or not hearing differences in the same material and systems depends on the quality of the systems the interaction of components and the experience of the listener. Most folks I know find the only way to deal with the overload in variables is to listen to a system over a week or so and your subconscious is good at detecting the overall cumulative differences. This is the only way I can do it reliably. Once you have identified the characteristics, they tend to be easier to pick out quickly. Unless you are comparing really cheap cables to really good cables on an otherwise really good system, an novist that does not want to hear a difference probably will not. An experienced person will.

 

Science only has a few of the variable defined as to their affect on the sound. They will all transmit the packets. While some companies have claimed to have identified the science, I would doubt what they have done is the end all to the science. After all in some cases, cables that, say retard the high freqency just a little could be a good thing. So, while in most cases a "better" cable is a better cable, sometime it might make a system sound worst... I have had this problem with systems that tended to be hard and brittle to start with.

 

Anyway, we resort to listening tests because, we do not understand all the scientific variables introduced, each system is very different, each listener is has differenct sensitivities. Muffled bass is a killer for one guy, while a little brittle high end will drive someone else crazy.

 

High end audio is connoisseurship. Connoisseurship enters when things are not cut and dried scientifically and usually when gestalt is the way to appreciate the individual components. Wine, if you had a printout of all the components in two bottles of great red wine, you would be not closer to answering the question of which is better. A great Monet is not better than a VanGogh because the is more cadmium in his yellows.

 

Differences exist and can be heard and it is useful when folks that can hear a difference can help the rest of us understand that difference so we can make better informed choices in putting together our systems without completely starting from scratch. JD

 

[losingmyreligion]

 

"Can we accept that not everything acts as it should do all of the time - or do they have a secret life all of their own?"

 

 

There's actually a much simpler explanation, to my mind.

 

Some assume that when things don't go exactly as predicted that some "law" has been broken.

 

 

Every time I hear someone invoke a "law of physics" to defend their claim that something someone else experienced could not possibly have happened, I'm reminded of the "moose crossing" signs I see on the road in northern Vermont. I see those signs and I wonder, who tells the moose where to cross? Shouldn't there be a schedule?

 

clay

 

 

 

[jacquesr]

And thanks to the schedule, only a small number of moose end up on the hood of passing cars. This proves that.

 

 

[losingmyreligion]

 

"Having a technically perfect reproduction system may indeed be counterproductive to achieving what you're trying to achieve."

 

I've always hankered for a preamp with a "resolution" control, so I could lower the resolution for less than impressive recordings, or a "musicality" control, to quickly turn your preamp into one of those that make all music sound sweet.

 

let's face it, tube-rolling is sooooo 1964.

 

clay

 

[losingmyreligion]

 

"There is of course a scenario where the cable affects the receiving DAC not by affecting the data, but by helping conduct RFI and electromagnetic noise into the DAC where it affects the internal operations in the DAC, but in that case the effects would be very much DAC dependent."

 

Agreed on the DAC dependency issue, but it's also dependent on one's entire environment, i.e. not just the DAC's sensitivity, but also the proclivity for the source and other gear to produce said noise.

 

I've been troubled for quite some time about the consistency in reporting - in the face of the dependencies - and especially troubling is the timeframe in which we've gone (at least on this site) from mostly saying / believing (as a consensus opinion) it can't make a difference to a significantly strong belief that USB cables are very important, even with Async USB. And this despite a glaring lack of correlation with Firewire cables.

 

Indeed, I don't think we've seen such a fast, massive shift in opinion since the winds shifted on whether software makes a difference.

 

For the record, I'm not saying that these things don't make a difference, but rather, I'm noting how quickly opinion has changed, and how dramatically the reported differences seem to have magnified.

 

 

clay

 

 

 

 

 

 

 

 

[barrows]

There are those who appear to be finding similar differences with FW cables, just peruse the Mytek DAC thread for examples...What, $4K Crystal Cable FW cables...

 

Anyway, I really wanted to respond (sorry to be OT, but it is an interesting anecdote to CG's and Clay's comments) about the "musicality" control.

One thing we flirted with back at PS Audio, was the idea of a class D amp with a "warmth" knob. This never got out of the prototype stage, as it was felt that marketing such a thing (with todays absense of tone controls, and audiphile belief that such things are "bad") would be problematic. But we had an engineer (brilliant guy, now working in another field of EE) who was certain he could easily develop a way to have adjustable low, even order, distortion in a class D amp, without having any other effects. Like a SET sound, just turn up the "warmth" control!

 

[Julf]

That article mostly talks about basic grounding issues - and if your system suffers from that, then it is rather badly designed. Anyway, balanced inputs and cables will take care of that. Then the author goes into stuff like triboelectric noise - relevant in an antenna mast with a lot of movement due to wind, less so in a living room.

 

Here is a good take on the issue from Bruno Putzeys, the designer of the state-of-art hypex class D amps - he knows a bit about what he is talking about.

 

Cable distortion and dielectric biasing