[Lapwing]

Quote:

Originally Posted by myinitialsaredac /img/forum/go_quote.gif Lapwing, Not to disregard you or anything, but there was actually a study conducted a while back on different HDMI cables and whether or not they could pass a 1080p/1080i/or 720p signal over a given length. I dont understand the finer points but the results did show that certain lengths of different cables experienced bit drop and could not transfer 1080 signals over 6 feet. Heres the article for you to gaze at - The Truth About Monster Cable, Part 2 (Verdict: Cheap Cables Keep Up...Usually). If there are differences in quality of HDMI cables, why then would there not be bit drop, electrical interference, or even bandwith choke or whatever it may be, on a USB cable? Dave

This article regards very long cables which are to be installed inside walls. It's well known that EM interference degrades electrical signals and cables which carry digital signals are no exception to this. The point in hand though, is that when a digital signal fails due to interference is fails completely, it's an utter break in the connection, a gap in the data stream. The result is a very noticeable loss of video or audio. EM interference on a digital cable WILL NOT "color" the data (the music or movie) in any way... your video WILL NOT look more vibrant or clear, your audio WILL NOT sound better in any way with better cables... the only thing better shielded digital cables will help prevent is complete video/audio loss. Thus if you use a cheap digital cable without experiencing any gaps in your video/audio you're set and any more expensive better shielded cable is entirely unneeded and a waste of money.

 

[tubaman]

Quote:

Originally Posted by Lapwing /img/forum/go_quote.gif This article regards very long cables which are to be installed inside walls. It's well known that EM interference degrades electrical signals and cables which carry digital signals are no exception to this. The point in hand though, is that when a digital signal fails due to interference is fails completely, it's an utter break in the connection, a gap in the data stream. The result is a very noticeable loss of video or audio. EM interference on a digital cable WILL NOT "color" the data (the music or movie) in any way... your video WILL NOT look more vibrant or clear, your audio WILL NOT sound better in any way with better cables... the only thing better shielded digital cables will help prevent is complete video/audio loss. Thus if you use a cheap digital cable without experiencing any gaps in your video/audio you're set and any more expensive better shielded cable is entirely unneeded and a waste of money.

How about vibration? Is it possible that vibration travels from the computer to the DAC and cause some kind of distortion, even when the data transfer is "complete?"

 

[rds]

Most DAC chips have a small amount of memory that holds something like 256 samples. The DAC plays the samples in first in first out order and the timing is clocked by the DAC.
The computer constantly tops up the sample memory on the DAC so it doesn't run out.
For a DAC like the Alien DAC (uses USB power), it might be worth considering how well the cable transmits power.

 

[joshd]

Quote:

Originally Posted by SleepyOne /img/forum/go_quote.gif There is definately a difference between the freebie USB cable that came with my DAC and the kimber. The freebie cable sounds muddy. I probably should as an experimnet try out other normal cheap USB cables to see whether kimber is really better or not.

Posts like yours are what is confusing people on the issue... because they are utter nonsense.

With a digital cable, either it transfers the data, or it has gaps in. Little dropouts. There is NO alternative. A cheap cable CANNOT sound muddy or distorted.

How many times do many different users here have to say this, before people will understand? I think you all need to make yourselves a nice hot drink, and spend the afternoon reading up on how digital signals in general work, with regards to USB/coax etc etc.

 

[tomb]

Quote:

Originally Posted by joshd /img/forum/go_quote.gif Posts like yours are what is confusing people on the issue... because they are utter nonsense. With a digital cable, either it transfers the data, or it has gaps in. Little dropouts. There is NO alternative. A cheap cable CANNOT sound muddy or distorted. How many times do many different users here have to say this, before people will understand? I think you all need to make yourselves a nice hot drink, and spend the afternoon reading up on how digital signals in general work, with regards to USB/coax etc etc.

I agree with rds's post above - the USB cable can make a huge difference in terms of S/N ratio and interference, if the DAC is USB-powered. I've measured up to a 20dB difference in S/N ratio between a run-of-the-mill cable and one that's shielded with chokes on both ends.

 

[joshd]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif I agree with rds's post above - the USB cable can make a huge difference in terms of S/N ratio and interference, if the DAC is USB-powered. I've measured up to a 20dB difference in S/N ratio between a run-of-the-mill cable and one that's shielded with chokes on both ends.

Yes, possibly with a DAC that runs from the USB bus's power, I can see the merit of a better cable. (But possibly not $500 better...?)

 

[olblueyez]

And if its not USB powered?

 

[joshd]

Quote:

Originally Posted by olblueyez /img/forum/go_quote.gif And if its not USB powered?

Then so long as you are not getting dropouts, more expensive cable makes absolutely no difference. At all.

 

[SleepyOne]

Have you considered the possibility the freebie UBS cable that came with my DAC may not be well made (up to standard etc), maybe that explains the difference in sound. And there is a difference between the freebie and the kimber. I am not saying kimber is great or anything - I still need to try out other normal UBS cables - but I am saying that it is possible to have a difference. Maybe this is due to timing (use of iron beads, silver plating etc) or noise or losses or whatever, no idea, this is what I hear. And frankly the result was a surprise to me too, maybe you should experiment to work out why.

As for the next question, cost and worth it or not, well I still have not decided. I need to investigate first.

 

[joshd]

Quote:

Originally Posted by SleepyOne /img/forum/go_quote.gif Have you considered the possibility the freebie UBS cable that came with my DAC may not be well made (up to standard etc), maybe that explains the difference in sound. And there is a difference between the freebie and the kimber. I am not saying kimber is great or anything - I still need to try out other normal UBS cables - but I am saying that it is possible to have a difference. Maybe this is due to timing (use of iron beads) or noise or losses or whatever, no idea, this is what I hear. And frankly the result was a surprise to me too, maybe you should experiment to work out why. As for the next question, cost and worth it or not, well I still have not decided. I need to investigate first.

Cheaply made or not, a poor quality will not and CANNOT sound "muddy".

You may have got breaks/dropouts in the audiostream, sure.

 

[SleepyOne]

I am going to get a belkin USB and if it sounds fine, then that will point towards the conclusion that my freebie usb cable is defective.

 

[joshd]

I'd have thought that people producing USB DACs would include a cable that is within spec and doesn't drop out.. :-/

 

[SleepyOne]

Me too but the world isn't perfect, hence existance of Watchdog on TV. And this is only a freebie that came with DAC so don't expect too much...

 

[Andrew_WOT]

What about jitter and transmission errors?
BTW, some interesting thread here, seems like some hear clear sonic difference between different USB cables.
Anyone do any USB Cable Comparisons
I probably wouldn't go as far as shelling out $500 for USB cable, but using some nice Belkin instead of el-cheapo cable that came with Stello DA100 was an inexpensive investment for some peace of mind.

 

[joshd]

Quote:

Originally Posted by Andrew_WOT /img/forum/go_quote.gif What about jitter and transmission errors? BTW, some interesting thread here, seems like some hear clear sonic difference between different USB cables. Anyone do any USB Cable Comparisons I probably wouldn't go as far as shelling out $500 for USB cable, but using some nice Belkin instead of el-cheapo cable that came with Stello DA100 was an inexpensive investment for some peace of mind.

Man, most posts in that thread were trying to point out that it makes no difference.

People who say things like:
Quote:

I could hear a difference. The Kimber was darker. The Belkin a tad brighter. Range and bass seemed similar but I preferred the Kimber.

Are either massive liars, possibly trying to persuade people to buy the cable because they work for the company? I don't know.


OK, I read the comments about it changing the leading edge, etc etc etc. It is possible for some bits to recorded incorrectly as a 0 or 1. This would happen randomly. Whatever cable you use, if it messing the data bad enough to change bits from 0 to 1 or vice versa, or mess up the timing because of accentuated jitter, it is NOT going to only affect the highs, leaving the bass intact.

The errors would be all over the frequency range, and there would be SKIPS AND DROPOUTS.