[Sonny]

http://www.lightharmonic.com/lightspeed.html#

Really???

[Devil Doc]

That link sends my anti-virus into spasm.

Doc

[Mike B.]

My experiments were simple. I bought two generic USB cables. They were identical model, manufacture and from the same vendor. I sent one to Jena Labs for cryogenic treatment. I then compared them. The cryo cord produced a more detailed or resolving playback IMO. Nothing scientific but enough for me to further explore the topic.

[mcgsxr]

I read a bunch on it when I was researching USB DAc's.

The consensus was that the Belden Gold was a cheap and good one.  I spent the $10 and have not looked back.

Could more $ yield better sound?  Sure, but the same can be said of my entire system, and I won't invest much in cables these days.

[Sonny]

That link sends my anti-virus into spasm.

Doc

Sorry, that shouldn't have done that, it's a link to the Light Harmonic website.

[Sonny]

I read a bunch on it when I was researching USB DAc's.

The consensus was that the Belden Gold was a cheap and good one.  I spent the $10 and have not looked back.

Could more $ yield better sound?  Sure, but the same can be said of my entire system, and I won't invest much in cables these days.

Thanks...I was just thinking that it's just bits...right?  If it's not right or timing is off, I guess it wouldn't work?
Where did you get the Belden gold?

[mcgsxr]

I am a purely subjective guy, I could not tell you how it works, or why to be honest.  I sometimes buy stuff for fun to see if I like what I hear.  What I like, I keep.  What does not do it for me, I sell.

Here in Canada I was able to pick up a 6 foot Belden Gold at the local Canada Computers (similar to an NCIX, or Tigerdirect).

I saw lots on eBay, but shipping to Canada doubled the price, so I hunted around locally.

My other cables are mid fi at best too, but out of what I spent, they are the ones I kept after playing around with some sub $100 interconnects.

[ThuanDB]

I had been using a Kimber usb for over a year.  Two days ago, listening to John Kenny's suggestion I tried a direct usb connection between audio PC laptop and his jkspdif3 converter.  No contest, case closed.  The $4 adapter loses nothing to the pretty good Kimber, only surprisingly gains in fuller body, separation, faster attack due to perceived blacker background (noise floor or jitter?), more detailed yet more listenable (unbelievable combo).  Its cost is over 60x less than the Kimber.

[loving_it]

I am a firm believer that different cables do make a difference but you have to have decent gear in order to hear that difference . I used a Audioquest Coffee and a wire world Platinum Starlight myself .

[*Scotty*]

In my system the USB cable is critical to extracting the maximum performance from my DAC. With the wrong design I can cripple the the systems performance. The sound-stage turns into musical wallpaper pasted on the front wall behind the speakers. The highs and lows can be missing in action and the dynamic life has taken a hike.
Scotty

[newzooreview]

In my system the USB cable is critical to extracting the maximum performance from my DAC. With the wrong design I can cripple the the systems performance. The sound-stage turns into musical wallpaper pasted on the front wall behind the speakers. The highs and lows can be missing in action and the dynamic life has taken a hike.
Scotty

Agreed. The USB cable feeding my DAC from my Mac Mini makes a noticeable difference. You have to remember that USB audio output contains no error correction (unlike USB data output from a hard drive to the computer). Sure, a file moving from a hard drive into the computer is just bits, but the data protocols for moving audio out of the computer are not the same. Also, the USB cable carries power, and it's a potential source of noise, voltage fluctuations, and disruption to the DAC. Not a technical explanation, but certainly there are reasons a USB cable can make a difference.

[santacore]

The Belkin Gold was my first attempt ag better USB audio. After noticing a positive difference with the Belkin, my search continued. I'm currently running a WyWire USB cable and think it's fantastic. It beat a few by Lotus Cables and Wireworld. For now, it's a keeper....that is until Alex of WyWires comes up with something better.

[figcon]

I ditto on the WyWires USB cable. I went from Belkin Gold to Pangea silver to Audioquest Coffee to WyWires and haven't felt the need to look anywhere else since. Great cable.

[Russtafarian]

Another vote for Wywires USB.

Recently I've been trying out some Linux-based USB streaming software (daphile.com).  Since it runs off a bootable USB stick, I tried it on three different laptops.  Each laptop, running the same program and playing the same files, sounded different.  I bring this up to suggest that variances in PC hardware are likely a big factor in the performance differences between USB cables.

Russ

[Nick77]

Recently switched from steaming with Touch to computer audio and Wywire USB cable, and new setup smoke's previous big time.

[mcgsxr]

I have run systems before with a higher investment in cables (I ran a Bolder Nitro rigged system for years) so I agree it can be found.

I'd say that your investment in your USB cable should reflect the balance of the investment in your system.

At present, I am way in the shallow end of the spending pool compared to where I used to be, but am enjoying the tunes a lot anyway.

I'd love to hear a Starlight, I hear very good things about them.

[kc8apf]

Agreed. The USB cable feeding my DAC from my Mac Mini makes a noticeable difference. You have to remember that USB audio output contains no error correction (unlike USB data output from a hard drive to the computer). Sure, a file moving from a hard drive into the computer is just bits, but the data protocols for moving audio out of the computer are not the same. Also, the USB cable carries power, and it's a potential source of noise, voltage fluctuations, and disruption to the DAC. Not a technical explanation, but certainly there are reasons a USB cable can make a difference.

Actually, the data protocols are the same.  The difference is in the transfer type.  Audio is isochronous while copying files is bulk.  Both contain error detection via cyclic redundancy checks (CRC).  In a bulk transfer, data correctness is considered more important than timing so error correction is done by retransmitting after detecting a bad CRC.  For isochronous, timing is assumed to be more important than receiving every packet.  That is, losing a frame of video is less noticeable than a corrupted frame.  So, the error detection still happens but the data is ignored and no retransmission is done.

So, yes a cable can make a difference but only when comparing against a substandard cable.  Anything that passes USB signal integrity testing should not experience errors.  To completely remove the cable from the equation, forward error correction could be included in the data packets.  Then a bad packet would be completely recoverable by the receiving device.

[newzooreview]

Actually, the data protocols are the same.  The difference is in the transfer type.  Audio is isochronous while copying files is bulk.  Both contain error detection via cyclic redundancy checks (CRC).  In a bulk transfer, data correctness is considered more important than timing so error correction is done by retransmitting after detecting a bad CRC.  For isochronous, timing is assumed to be more important than receiving every packet.  That is, losing a frame of video is less noticeable than a corrupted frame.  So, the error detection still happens but the data is ignored and no retransmission is done.

So, yes a cable can make a difference but only when comparing against a substandard cable.  Anything that passes USB signal integrity testing should not experience errors.  To completely remove the cable from the equation, forward error correction could be included in the data packets.  Then a bad packet would be completely recoverable by the receiving device.

That's a long-winded way of confirming what I said.

1. USB audio does not correct errors. You mention error "detection" but it's not relevant that an error is identified: when there's an error, a USB audio data transfer will simply drop the packet and keep going: timing over data integrity. Very few people seem to recognize this difference. If you want to say its a difference of "transfer type" and not "data protocol" then fine. Call it "wooly wombat" for all it matters.

2. USB cables carry power as well as data. You didn't discuss this but it's equally important. Even if the DAC isn't powered from USB (although many are), the voltage fluctuations and noise over the cable can affect the DAC's power supply and affect the integrity of the data signal.

[kc8apf]

That's a long-winded way of confirming what I said.

That likely depends on the reader.  There is a lot of subtlety in USB and the terminology matters.

1. USB audio does not correct errors. You mention error "detection" but it's not relevant that an error is identified: when there's an error, a USB audio data transfer will simply drop the packet and keep going: timing over data integrity. Very few people seem to recognize this difference. If you want to say its a difference of "transfer type" and not "data protocol" then fine. Call it "wooly wombat" for all it matters.

No need for quotes around detection.  That's exactly what it is and it is quite relevant.  If there was no error detection, a single bit flip in the most-significant bit would cause a huge swing in the DAC output.  Instead, the sample is omitted and the DAC will do something more reasonable like hold the previous sample's value.  It doesn't get you bit-perfect playback but it makes any errors _much_ more pleasant.

FWIW, USB doesn't prevent bit-perfect transmission.  A DAC designer could implement it using bulk transfers and avoid the whole problem.  Buffer enough in the DAC and a moderate amount of errors can be recovered from via retransmits.  If you are really concerned about synchronization with video playback, use isochronous transfers with forward-error correction as part of the data packet.  I'm guessing the reason no does this is that errors don't really happen that often with average cables.

2. USB cables carry power as well as data. You didn't discuss this but it's equally important. Even if the DAC isn't powered from USB (although many are), the voltage fluctuations and noise over the cable can affect the DAC's power supply and affect the integrity of the data signal.

That depends on the design.  A self-powered DAC has no need for the USB power.  They could be left unconnected.  Only the data lines are actually needed.

[newzooreview]

No need for quotes around detection.

Of course there's a need for quotes. Your intention was to contradict the statement that USB audio doesn't have error correction, but you spoke about error "detection." I quoted your deceptive shift in terms to make sure that it was clear what you were doing. Same point regarding "data protocol" versus "transfer type" -- it only serves to muddy the discussion. The point that USB handles the movement of data differently for audio is what is relevant here.

Please note that in posts above some people are convinced that "bits are bits" and any USB cable will transfer the bits accurately and completely to the DAC. That is not the case.