High End USB Cables - Real or Fantasy?

Others will disagree, but of course there is no difference.

I think it is the one cable that Monster doesn't make yet so there must really be no difference (or more appropriately a marketable difference, not audible). 

Not sure - I've been running a dealer-supplied Audioquest usb cable from the start, never tried anything else. I have a sneaking suspicion that differences are subtle if there at all, however, BNC/SPDIF cables clearly have their own signature so wouldn't discount the same for USB altogether. 

EJ

Interesting.. The so called sound quality is really determined by how susceptible your audio equipment is to interference, Powerline intermodulation, RF and EMI. If your equipment is immune from this (in the real world almost impossible) then different USB cable characteristics should give no variation in SQ. But since USB (1 and 2) is a reasonably loose standard in terms of physical electrical characteristics, USB leads will most likely therefore give the appearance of 'sounding' different, albeit it's their physical electrical properties affecting the performance of connected audio equipment.

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So a well designed lead with a quality twisted differential signal pair, perhaps shielded and suitably decoupled powerlines into a quality USB connector could perform electrically better than a cable that wasn't as carefully, but still compliantly constructed.

However, the price of this should be minimal, and of course in this market anything slightly different has exponential margins and great scope for rip off.. Especially if it looks pretty.

BTW the same principle applies to USB memory sticks.

Simon

Isn't it also the case that many DACs take a 5V supply from the computer to power the USB interface, and that 5V supply is unlikely to be of the highest quality. In which case, mightn't USB cables that come with their own higher quality 5V power-supply, like say the ifi-audio iUSB, offer some advantages? 

From my past experience they do make a difference; not night and day of course but potentially significant.

As long as it says 'Belkin' on the packaging, it's OK for my NDS & HDX !

But this is a thread that I shall watch with interest - as I've mentioned before, my ears are of the pink, not golden variety. 

I bought a Wireworld USB A-B around £45 on recommendation of friends.

I think there was a slight increase in SQ but the main difference was that the plugs fitted a lot better.

So maybe the performance is in the plugs not so much the cable?

Poor socket fit had included "Belkin" too.

If the USB performance was so susceptible to cable construction - how come data loss is not common when working with computer files? Is it the interface software used in audio that is inadequate then, requiring extra dressing just for audio data?

+1

I was getting audio breaks and unreliability with previous USB cables , much more reliable with the wireworld.

Make of that what you will!

Does it matter in the end....

I am asking the same question. Obviously, some people find that there is difference in cables, so I believe it, but I'm having hard time to understand why, and how. 

I wrestled with the 'how' question as I like to know how things work.  The research led me an understanding that audio data is a stream, but I have not heard an explanation as to how this translates to asynchronous audio data.  

One thing for certain is that jitter and EMI reduction is what makes the difference in audio and that what the cables are designed to minimise.

BTW, I end up choosing a Wireworld cable (Starlight 7). It took a long time to run in compared with the Audioquests.  I guess there is much more shielding that has 'burn in', which is said to be part of the electric circuit.

More food for thought.

Almost anyone who has used a USB device at sometime has encountered a "bad" cable for at least one of a multitude of reasons ranging from:

1. Not supporting the 5V power standard (if the device on one end is to be powered in this fashion). A lot of USB2 devices still are shipped with an external power supply (usually a "wall wart") precisely for this reason.
2. Poor connectors on the cable (or misshappen from improper storage; even more of a problem with the new USB 3 connectors and these cables are so terribly short, must be due to the wires being used being extremely thin even compared to the USB 2 standards)
3. poor connectors on the device itself (tend to break off or break the circuit boards if too much force is used or from muliple connection/reconnection or if someone transports the device with the USB cable in place)
4. poor adherence to standards (ie. too cheaply made)
5. other problems in the manufacturering process.

In a tightly bound multi-conductor wire package like the USB cable in general (there are not surprisingly flat USB cables now available on the market from some of the mainstream computer cable manufacturers, often labelled as high performance data cables) crosstalk can be a major issue.  I can see some benefit from cables where the design decreases or eliminates to vanishingly small levels the potential for crosstalk, and also improves on the "fit" of the connectors,etc.  All of these should be very measureable improvements (and also probably audible), but alas, the manufacturers of these cables are probably not going to publish or list these specs or design benefits on their packaging. 

There is little doubt that improved connections, particularly if the material making the connection is the same throughout (same on the cable and on the device being connected), will improve electrical throughput, how audible this is will definitely be a subjective battleground. I suspect only the most "golden eared" of audiophiles will actually claim/hear a difference that can be described as more than very subtle, if subtle at all. 

These same issues will also extend into the realm of internet cables (cat 5 vs 5e vs 6, etc.) I would suspect, but given the longer runs and other issues with their use and installation, probably more measureable and audible in certain instances.

What I am also curious about is those who have reported "dropouts" etc with USB cables, what material have they been playing back at the time (low res MP3, hi-res 192KHz or what?)? As an earlier post has  mentioned, are the software drivers for the interfaces up to the challenge of "pushing" this data stream through the cable without overloading their own data buffers or the physical limit of the cable itself? (are we pushing the technology with some data transmission and hence "loosing" or changing the data).

Jitter will be a potential problem for digital transmission along a USB cable (computer to DAC, etc.) but not for analog audio.

In the interests of scientific research, you understand, I have recently set up a new office music system with a 2012 mac mini playing music via iTunes & the Bitperfact app through a new Naim DAC-V1& NAP140 into a pair of wall mounted PMC DB1i speakers.

I have used a USB cable to connect the mac mini to the DAC-V1.  It is really, really cheap.

The DAC-V1 and NAP140 are both powered from a SMPS infested ring main (at least 15 SMPS on this ring main) via a cheap DIY store 4 way mains distribution block and Naim mains cables.

Given such care with set up, the sound quality is, as you might image, simply brilliant

Having met Touraj, liked him and as I really enjoy my Roksan turntable, I've ordered a Vertere Pulse D-Fi USB cable (yes, it's a posh one!)

I'm also having a mains radial circuit installed for the new music system.

It will be interesting to hear the differences that these 2 changes make.

Best regards, FT

Couldn't quite work out issue about data loss and compliant cable construction. The specification has quite a loose standard as I said.. I was talking about EMI and coupled RFI which is quite separate... .??????

But any if there is a bu error through signal error the receiver flags it and asks the sender to resend, so you USB flow control and retry. It's quite a neat standard.

Simon

Interesting, so there theoretically shouldn't be any difference between a so called "crappy" cable and a "hi-tech" one except if the cable (or circuit) is physically broken at some point impeding the transmission.  Very neat.

So Foot Tapper, when the reno is completed, you should be able to switch USBs and there should be no audible difference other than those associated with the USB standard for flow control and retry.  I suspect the dedicated mains will make the usual documented improvement in sound quality.

Hi, not quite my meaning... A less optimum USB cable can be within the USB specification and work as intended, but can be more prone toi causing and be affected by interference and physical electrical transmission issues such as coupling, imbalances and reflections. These parameters can effect the connected equipment.

The USB standard has a means of error detection and  data retransmission. Therefore with a less perfected cable (but still compliant), or a cable working in a hostile electrical environment or near the edge of the USB specification the probability of signal degradation causing a bus error, and data retransmit is higher. 

Interesting point to me, I don't know without looking it up how data retransmit protocol works in asynchronous mode if at all, unless anyone wishes to share on here...

Simon

Edit. My curiosity got the better of me.. In asynchronous mode, which uses the USB isochronous transfer mode, there is no handshaking or retransmit protocol. There is simply a CRC check to discard the frame on signal corruption... Not dissimilar to SPDIF or Ethernet layer 2 frames for that matter.

There's a group  test ( blind listening auditions) of USB cables in the July edition of Hi-Fi-News.

Prices range from £18 to a gob smacking £6500.

In the same edition Paul Miller, the editor,  has publish a one page article on how he produced and conducted the necessary technical tests.

Just the booksellers here and they only have the May issue, guess will have to wait about 2 months for the July issue to show up on this side of the Atlantic.