usb cables?

[PeterSt]

23 minutes ago, marce said:

Digital carries the analogue signal as packets of information in binary format, noise can be superimposed on the signal but does not become part  of the analogue information and within easily achived tolerances the noise will not alter the transmitted information.

 

Too bad that 8KHz packet noise is right in the audio band. So via the backdoor it *does* become part of the "analogue information". If anything is easily measurable it is that.

And this is just one aspect (but IMO the easiest to see and understand).

Then even this one is already complex because it is about what the digital information including noise IMPLIES. And that "at the other end" (behind or even within the USB receiver).

 

As long as these aspects are not understood, all USB cables will sound the same. Especially if you don't attempt listening to a couple.

[PeterSt]

15 minutes ago, JanRSmit said:

How do i as enduser know the always present noise is not interfering? 

 

Oh, but you do know. I just tell you. Hahaha.

 

The key is in the "always present" because although it is, it is always different (incurred for by environmental settings and even explicit settings (like in-software)). And btw, although a lot is USB specific, an other lot is not related to USB at all.

The skill about controlling it and slowly we get further and further with that. According to some, however, nothing happens. 

[mansr]

18 minutes ago, PeterSt said:

Too bad that 8KHz packet noise is right in the audio band. So via the backdoor it *does* become part of the "analogue information". If anything is easily measurable it is that.

The packet noise is created by the USB receiver. Nothing to do with cables.

[One and a half]

4 hours ago, musicguy said:

@One and a half  A lot of what you here, is what i have experienced with my own usb cables.  The pangea ag,  sounded very slightly bloated but no sound stage and the treble was very reduced.  No air to the sound.  AQ forest just a bit smoother over a standard well made cable.  WW starlight 7.  Very good cable but lack bass.  AQ cinnamon was the best overall sounding cable i have.   Most balanced.   

 

I have been reading many post,  Sorry I open this can of whoop ass on myself,  AQ coffee, Cardas clear,  Blackcat cables,  Lush, Curios and nordost.     There are so many usb cables now.   Thats why i started this post.   I am here to impove my sound.  Not to get into a war about cables or if they even do anything.  I have been in the high end side of audio for 35 years.  Everything can effect sound.   I now have a very good source mac mini.   Now i hear that my usb cable is the weakest link.  Im not looking for the most expensive cable either.   The Silver usb from blackcat cables,  always performs way above its price point. 

 

 

Yes it’s that variability that infests USB, the noise is always there from the source to the DAC and even the other way around, the USB cable with its great shield is a conduit for noise to pass freely.

 

After much deliberation, a network renderer was bought now 7 months ago, and did not need to use USB any more, haven’t looked back. That level of grunge is gone, and the cabling is not as fickle if the paths are simple, makes listening a joy, provided the recording doesn’t have too many flaws ....

 

The best way to improve USB is not to use it.

[marce]

1 hour ago, PeterSt said:

 

Oh, but you do know. I just tell you. Hahaha.

 

The key is in the "always present" because although it is, it is always different (incurred for by environmental settings and even explicit settings (like in-software)). And btw, although a lot is USB specific, an other lot is not related to USB at all.

The skill about controlling it and slowly we get further and further with that. According to some, however, nothing happens. 

Maybe you should look up the likes of Henry Ott or Ralph Morrison...

[marce]

1 hour ago, mansr said:

The packet noise is created by the USB receiver. Nothing to do with cables.

Thank you, these discussions do tend wander...

[sandyk]

1 hour ago, PeterSt said:

As long as these aspects are not understood, all USB cables will sound the same.

 

If no bit errors, they will all sound the same, at least to Mansr

7 minutes ago, One and a half said:

The best way to improve USB is not to use it.

 

Unfortunately, some are forced to use it if they want DSD.

[marce]

2 hours ago, JanRSmit said:

So , to understand what you are saying, in the case of digital info, noise (which is always present) will not somehow interfere if it stays below a certain level. Then the questions i have:

How is this achieved in essence?

does the noise spectrum make a difference?

Is this true also for computer to dac communication?

How do i as enduser know the always present noise is not interfering? 

The reference is to noise superimposed on the digital signal, not EMC engineering of a system. The comment is reffering ton the signals travelling down a wire and comparing an analogue signal to a digital signal and the effect of noise on these signals. If the eye opening of a digital signals eye diagram is within the required specification then the digital data will get through.

System noise problems comes under EMC engineering, well studied, very well studied, lots of information out there on EMC.

[asdf1000]

If the USB source is battery powered (disconnected from AC mains power) I wonder how much a system would sound different with all these different USB cables?

 

Easy to test with a laptop as USB source (all other cables disconnected). Or even a mobile phone/tablet (turning off WiFi and cellular radio for the test).

 

No ground / leakage currents...

 

Of course I know it's not always practical to have a battery powered USB source - can be a pain in the a$$ if you need to re-charge a battery all the time.

[luisma]

This is such a polemic topic, honestly any thoughts of my own (and I have a strong technical education and experience) are controversial even to myself. I have experienced with data traffic things that if you look at it in a superficial manner you could get some results and these would differ completely from the real results and though USB data transfer it is pretty straightforward as a protocol there may consequences of external factors (cable, noise, EMI/RFI) which could potentially affect the equipment connected with such USB cables. 

[JanRSmit]

57 minutes ago, marce said:

The reference is to noise superimposed on the digital signal, not EMC engineering of a system. The comment is reffering ton the signals travelling down a wire and comparing an analogue signal to a digital signal and the effect of noise on these signals. If the eye opening of a digital signals eye diagram is within the required specification then the digital data will get through.

System noise problems comes under EMC engineering, well studied, very well studied, lots of information out there on EMC.

Tanks for pointing to eye diagram. Two main causes are jitter and noise, perhaps also signal strength. This is under the assumption that the cable and plugs and receptacles themselves and together function flawlessly. Correct analysis?

[fas42]

Have never used a USB link in audio, but everything I've read of people's experiences makes me very suspicious of the plug and receptacle arrangement - one of the first experiments I would do if I were to pursue this aspect of audio would be to remove this mechanism from the link entirely; that is, hardwire the cable to the circuitry at both ends ... does this make a difference?

[adamdea]

3 hours ago, JanRSmit said:

So , to understand what you are saying, in the case of digital info, noise (which is always present) will not somehow interfere if it stays below a certain level. Then the questions i have:

How is this achieved in essence?

does the noise spectrum make a difference?

Is this true also for computer to dac communication?

How do i as enduser know the always present noise is not interfering? 

Taking this question at face value, the answer to your question is that noise in a digital infromation system does not (until it reaches a treshold level) interfere with the signal because it is a digital information system.

There is a very easy way to understand it which is to forget what you think you know and just consider everyday numerical and symbolic information like numbers on a page.

 

Write the number 1 on a piece of paper. with a pencil. Show it to someone and ask them what number is on the paper (from 0 to 10).

Try making the line slightly wiggly and vary its length . How wiggly/ short/long  does the line have to be before the reader is unable to identify the number as a 1.

Repeat the experiment asking the reader to identify whether the shape you have drawn on the piece of paper is a 0 or a 1.

How does this affect the threshold of wiggliness/length?

 

The information content of a symbol (number/ digital signal) remains the same despite large amounts of distortion or variation in the carrier medium (pencil marking/signal voltage). There is no particualr reason why symbolically encoded information SHOULD be affected by variations in the carrier medium (wiggliness/noise) provided that the symbol can be read. Where there are only two possible values (o and 1) you can have one hell of a lot of noise without affecting the ability of the reader to identify the 0s and 1s.

 

Provided that you have correctly read the data you have a complete record of the song. There is no further information required for reproduction of the song. How can changing usb cables make any difference provided that the data can be read? There are a number of ways of verifying that information is perfectly transmitted. It can be done by sending DTS encoded files, and some dacs have diagnostic files to check (eg an Mdac). The major purpose in the diagnositc files is to check for unexpected resampling /dsp in your computer, because the usb cables will transmit the data fine. If you get a sum wrong, it is probably not because of the pencil you use.

This is very easy to understand as long as you forget all the audiophile bull. Interesting factoid: Shannon's proof of the sampling theorem is contained within a paper entitled "Communication in the Presence of Noise"

 

 

[manisandher]

41 minutes ago, adamdea said:

... the answer to your question is that noise in a digital infromation system does not (until it reaches a treshold level) interfere with the signal because it is a digital information system.

 

No one disputes this. All audio USB cables will (unless the aforementioned threshold level is reached) transmit the digital data perfectly. Keep things in the digital domain, no problem.

 

However...

 

Things seem to go awry at the exact point of digital-to-analogue conversion. Different USB cables seem to affect digital-to-analogue conversion in different ways. The exact mechanism at play? I'm not sure. Maybe noise getting into the DAC chips on the back of the USB signal, or perhaps some sort of radiation having some sort of effect.

 

But one thing is clear - different USB cables sound audibly different.

[audiobomber]

I've listened extensively for differences in USB cables from Oyaide, Ghent Audio, Vangard, Korg and several generics, including dual-head and USB 3.0. I hear significant differences among all of these in my main system and in my dedicated headphone system. I agree with whoever said that cost is not a determinant of SQ. Powering the DAC separately from the digital transport with a USB cable or iDefender is sometimes a major improvement, sometimes unnecessary. 

 

In my headphone system, I replaced a Ghent Audio dual-head USB cable with a USB A to B adapter (no cable, just a simple adapter), in my dedicated desktop system. The adapter is USB 3.0 because that is what iFi recommends with their iPurifier. I heard an immediate improvement in PRaT due to faster transient release and decay. 

 

I am very pleased with the Oyaide neo+ Class A in my main audio system, where it outperformed a more expensive Oyaide neo+ Class S cable and other USB cables mentioned above. If I could accommodate it physically, I would replace the Oyaide with a Sonore USB adapter. What is especially appealing with the Sonore is the 5V bus blocking switch. I use electrical tape to block the 5V pin on the Oyaide, which provides a significant improvement in the sound. My DAC does not use USB power and does not manage it well. YMMV, but do try blocking the USB 5V if your DAC is self-powered.

[Ralf11]

7 hours ago, JanRSmit said:

So, enlighten us with some basics relevant for computer-dac communication.

For one i know that with usb cable use between computer and large format printers, the USB cable quality does matter.

 

I'll paraphrase what Peter said:

 

Noise cannot affect the digital signal itself (as a practical matter; if an EMF pulse bomb goes off near your USB cable then all bets are off).

 

A USB cable also has a ground wire, and noise can be transmitted to the DAC along the cable (optical does not have this problem).  Now, what happens to the noise once it gets into the DAC?

 

Once in the box, the noise can affect very low analog signals just after the digital to analog conversion occurs.

 

(There are some other possibilities, but this is the easy version).

 

When you isolate the DAC from any noise sources, you solve the problem.

 

Besides the USB cable, there are other ways that noise could possibly get into the DAC: radiation thru the air (highly unlikely i most situations), and via the AC power cable (AC line, aka mains).

 

Putting the DAC on a different AC circuit than the server (computer) attenuates the AC line noise to the DAC.  However, this may well not be a problem, tho it is good practice.

 

 

So... if you have isolated the DAC from all 3 possibilities of noise injection different USB cables (that meet the spec.) will not make a difference.

 

Differences are perceived either because of confirmation bias or because they actually exist due to lack of isolation.  Double blinded and properly conducted listening tests would tell you if the former was the reason, but are rarely done.  AND, it may be easier to buy an inexpensive isolation device than to conduct the test.

[adamdea]

57 minutes ago, Ralf11 said:

 

I'll paraphrase what Peter said:

 

 

So... if you have isolated the DAC from all 3 possibilities of noise injection different USB cables (that meet the spec.) will not make a difference.

 

Differences are perceived either because of confirmation bias or because they actually exist due to lack of isolation.  Double blinded and properly conducted listening tests would tell you if the former was the reason, but are rarely done.  AND, it may be easier to buy an inexpensive isolation device than to conduct the test.

leaving aside cables which cut off the ground and/or 5v, it is worth bearing in mind that most cables contain conductors which are generally made of metals chosen for their property of conducting electricity. So the only thing which any of these cables can do with noise is to conduct it. This will not get any better by making the conductors out of silver rather than copper, or having a fancy dieletric or giving the conductors a much bigger diameter. Compare eg various audioquest cables at different price points. Supposing that there is noise coming from the computer source and the dac is sufficiently badly designed to allow this to reach its analogue output, thus essentially negating its purpose as a digital audio device. How will a fancy cable help by conducting the noise slightly better? Just saying.

[musicguy]

Im getting a blackcat usb "silverstar usb"   on monday.   

 

I know this cable is out of production in 10 years.   SOO????

 

Ill report back here on monday.   

 

musicguy

[musicguy]

hey guys,   

 

please dont  attack anyone here. 

 

do you have a good review of a usb cable or not

 

musicguy

 

[The Computer Audiophile]

Thread has been cleaned up. People are wasting their own time and mine by posting comments in this thread that are not wanted by the OP.

[RickyV]

4 minutes ago, musicguy said:

Im the original poster of this thread?

 

May  I kill it.   Im tired of my email blowing up.

 

I dont care if you believe in science or cable theories .   I just wanted to know if you bought a cable and you thought it sounded good.

 

musicguy

 

Hahahaha, sorry you had to go true this, cables is a sensitive subject around here.

good luck with your search 

[musicguy]

 

current top performing usb cables?

 

musicguy

[RickyV]

Sorry I have just tried two, the lush and the lush^2, oh and a 1$ cable.

The lush^2 is the best of cause  but what amazes me is that the different shield configurations changes the sound.  Some give a more articulated bass, some are better  in highs or just overall more spacial. It is clearly audible.

Did you read the lush thread?

[Blake]

3 hours ago, musicguy said:

hey guys,   

 

please dont  attack anyone here. 

 

do you have a good review of a usb cable or not

 

musicguy

 

 

Hi musicguy.  I am 100% in the camp that different usb cables can impact sound quality based on my own buying, trying, selling experiences.  Having said that, I have no issue with any of my fellow AS members who are not "believers".  My favorite is the Sablon Reserva.

 

This is the best (and longest running) usb cable comparison thread here on AS, imho, so take a look:

 

 

 

[fas42]

3 hours ago, musicguy said:

 

current top performing usb cables?

 

musicguy

 

From where I'm coming from you're asking the wrong question - it's akin to having unbalanced wheels on your car, and asking people what are the best cushions to sit on so that you can't feel the vibration coming through the seat ...

 

IOW, it's vastly more effective understanding why there's a problem, and then doing something, perhaps quite trivial, which eliminates the issue completely - i.e. take the car to a tyre dealer, and get a low cost rebalancing.

 

People in the audio game either believe that there has to be a magic solution, preferably ridiculously expensive, , or thump the table ferociously, declaring that it's impossible for there to be a problem in the first place! It's a nutter's world, and most sane people steer well clear of it, . Rationality plays only a small part in the mix, and so the Days of Our Lives continues ...

 

If I was determined to make having the 'right' USB cable The Solution, I would buy every single cable that was out there that had a money back guarantee, hundreds if necessary, and try them out one at a time, to find the particular item that just happened to be most effective in that rig, for whatever reasons completely unique to that setup and environment. If half a dozen happened to be a good match, pick out the prettiest ... and send all the rest back, .