This is going to upset a lot of people....
On Wednesday last week I listened to a demo of a system with two different USB cables....... and they did sound different.
The source with a medium spec laptop with USB 3.0 out. I think the software player was iRiver, but I'm not 100% sure on that. Music files ripped as WAV.
The audio hardware was
Teac UD501 DAC running on 44.1kHz
LINK £600
Onkyo P-3000R 2 ch pre-amp via analogue in on phono/RCA
LINK aprx £1000
Onkyo M-5000R 2 ch power amp
LINK £2,500
KEF Reference 203/2 speakers
LINK £4000/pr
The two cables heard were:
Chord USB SilverPlus (£45)
LINK and the Chord Signature USB Tuned ARAY (£400!!)
LINK
Now, before the usual chorus chime in their disapproval, some other background info....
I wasn't looking to hear this as a demo. I'm not looking for any kind of USB cable for audio, so I have no interest in either. This was something that happened to be going on in the store as I came in to calibrate a projector. The listening was being done on the sales floor of the shop, so there was a bit of street noise. The shop floor had loads of other speakers and TVs around. i.e. this was not some kind of specialist dem room. The mains was as dirty as you like. The pre-amp volume was left set, as were the DAC settings. The only change in the system was pausing the music and swapping the cable.
The music selection was varied. Some Blur, Beatles, Miles Davis, Mary Chapin Carpenter amongst others.
I haven't heard the £45 Chord cable against a bog standard USB cable, so I can't comment on that.
The first track up was Blur's
Boys & Girls from the album
Park Life. It was played on the £45 Chord. Then the cable was changed to the £400. TBH, I was quite shocked at the difference. Suddenly notes and sounds had a shape and layering effect that at first was quite jarring. There was positional space between each thread in the mix, and instruments had a very defined position both in width and height. There was no real sense of front/back depth to the soundstage from either cable. That may be more to do with the environment though.
At first I found the sound too brittle, too unrelenting. It was possible to pick out all the faults in Albarn's vocal. There was a strong sense that this was a multi-tracked recording where each player's contribution was recorded solo to a backing track and then mixed together in post production. The cheaper cable was less ruthless but also lacked the precision. The vocal wasn't as pin point and the small details in the sound weren't there.
Later we tried the Miles Davis track
So What from the album
Kind of Blue. The recording is from 1959. This would have been recorded as a single pass with all the more expensive cable was somehow allowing a cleaner signal through that offered more insight in to the recordings.
I have some sympathy with those who say digital is digital. In the wrong system then I think it would be easy to come to that conclusion. This goes for the differences in a lot of electronics too. Even as I listened to and fro on the same tracks I got accustomed to the two different sounds. Speakers make such a big difference to the presentation of the sound that any system would have to be very broken to mask those differences. But I can see how the differences between electronics can be glossed over. So I fully expect there'll be a lot of folk who'll say this was all placebo. It's pointless wasting time on the same old arguments. The other often quoted line is "It makes no difference to my printing". Quite correct. If the data flow for printing was as fast as for music then a document would be sat ready in the print tray before the finger bottoms out the print key or mouse click. They're two very different things.
USB has just two connections for the data signal (Data +ve and Data -ve) and uses differential signalling which is the same principle as balanced audio to get rid of noise picked up on the line. That doesn't eliminate data errors though. So my gut feeling is that the error correction inherent in USB can be heard. The less hard it has to work then the the cleaner the signal.
[Dons flame-proof suit and awaits the onslaught

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