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SteveR750's picture
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RE: USB cables, please share your experience

What about jitter?

 

I'm pretty sure my DM+ sounds better vua USB than it does using the toslink connection, which mostly due to a limited understanding of how the data is streamed down have assumed because there is inherently more jitter using optical than async USB. Of course, how the device (DAC in this case) handles jitter, and how the streamer is presenting it must play a big part.

 

I admit I really struggle to understand the concept of timing error due to flattening or rounding of the pulse wave which presumably is the only way a cable could have some influence. Not that I'd spend any money an expensive cable even if proven to be better, as I can't hear any difference....

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RE: USB cables, please share your experience

Wow!  So many posts in so short a time.  Great fun!

Chris

 

Marantz PM8005 / SA8005 / KEF R700s / AKG K702

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RE: USB cables, please share your experience

Maybe the DM has a great USB implementation - theres no way we can tell, thats the problem.

Optical is my connection of choice, no electrical connection to the dac and nice thin cable if nothing else.  As for jitter, yes tried to get my head round that myself but apparently you need 2 atomic clocks and a flux capacitor to measure it between 2 devices lol.  :grin:

If only USB used buffering and data acknowledgements (like ethernet) the usb cable debate would be a short one.  Unfortunately, it doesnt to my understanding.  The only reason why ethernet is so successful is because the protocols that govern the data transfer are rock solid.  Data gets through, even over some clapped out cable.  

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RE: USB cables, please share your experience

I'm pretty sure the implementation in the device is more critical than the USB cable by some margin. The Chord DAC, and for that matter the NAD and the M-DAC sounded best via optical (if only because the M-DAC was somewhat user unfreindly via USB in my opinion).

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RE: USB cables, please share your experience

SteveR750 wrote:

What about jitter?

 

.....

 

There have been a few studies on the audibility of jitter, but as it is measured in pico seconds, or onr trillionth of a second and there are many calims of virtually eleiminating it, how audible is that realistically going to be?

 

In any case, there is still the issue of the massive gaping hole of a missing link, a causal link between electrical properties of transferring a digital signal and subjective reports of sound quality. There is no evidence that a certain level of jitter affects bass, or treble, or soundstage or anything like that.

SteveR750's picture
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RE: USB cables, please share your experience

idc wrote:

SteveR750 wrote:

What about jitter?

 

.....

 

There have been a few studies on the audibility of jitter, but as it is measured in pico seconds, or onr trillionth of a second and there are many calims of virtually eleiminating it, how audible is that realistically going to be?

 

In any case, there is still the issue of the massive gaping hole of a missing link, a causal link between electrical properties of transferring a digital signal and subjective reports of sound quality. There is no evidence that a certain level of jitter affects bass, or treble, or soundstage or anything like that.

 

I'm sure I've read somewhere that (at sufficient levels) jitter adds a level of harshness / lack of treble smoothness and clarity. I thought that this was one major reason why cheap DACs (think phones / PCs) sound so inferior, because of their poor quality clocks. 

http://www.positive-feedback.com/Issue43/jitter.htm

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RE: USB cables, please share your experience

SteveR750 wrote:
I'm sure I've read somewhere that (at sufficient levels) jitter adds a level of harshness / lack of treble smoothness and clarity. I thought that this was one major reason why cheap DACs (think phones / PCs) sound so inferior, because of their poor quality clocks.

Even at 50 nano seconds, sinusoidal jitter was concluded to be subjectively inaudible (between 30Hz - 16KHz) to 95 percent of listeners according to this 1974 BBC R&D report...

http://downloads.bbc.co.uk/rd/pubs/reports/1974-11.pdf

If jitter is still causing audible problems - after 36 intervening years of progress - then i'd be amazed.

"We are currently awaiting the loading of our complement of small lemon-soaked paper napkins for your comfort, refreshment and hygiene during the journey."

SteveR750's picture
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RE: USB cables, please share your experience

chebby wrote:

SteveR750 wrote:
I'm sure I've read somewhere that (at sufficient levels) jitter adds a level of harshness / lack of treble smoothness and clarity. I thought that this was one major reason why cheap DACs (think phones / PCs) sound so inferior, because of their poor quality clocks.

Even at 50 nano seconds, sinusoidal jitter was concluded to be subjectively inaudible (between 30Hz - 16KHz) to 95 percent of listeners according to this 1974 BBC R&D report...

http://downloads.bbc.co.uk/rd/pubs/reports/1974-11.pdf

If jitter is still causing audible problems - after 36 intervening years of progress - then i'd be amazed.

(I edited my post in between your reply)

Who knows? Steve Nugent isn't sure, though seems was was right about USB becoming the prevalent choice of streaming protocol.

 

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RE: USB cables, please share your experience

This is my 2 cents on this subject....shoot or dont shoot me...but thats what I experienced with this USB cable.

http://notanotherhifiblog.blogspot.com/2012/12/kingrex-unanimous-u-art-y-usb-cable_25.html

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RE: USB cables, please share your experience

You listen to 100 hours of music per week? That's 14 hours a day!!

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RE: USB cables, please share your experience

BenLaw wrote:

You listen to 100 hours of music per week? That's 14 hours a day!!

 

Hey....I did mention '...I didn’t actually time myself to reach 300 hours but after about 3 weeks of listening, ...'

Physically, there was data running through the cable 24-7 for 3 weeks as I put on itunes on repeat....but I would say I spent about 2 to 3 hours a day listening to music on weekdays...and about 4 to 5 hours on weekends...

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