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Synth80s · 30th March 2006

One more thought: I'm using my optical cables to run 16 channels back and forth between a digital mixer and my computer. I think we can all agree that Bob Katz is an authority on all things digital audio -- I'm still reading his excellent book, "Mastering Audio."

Bob states that jitter is not introduced over toslink between digital devices because they don't pass clock, but that A/D and D/A connections are the critical paths where digital cable makes a difference. I use word clock all around and Canare S/PDIF to my A/D and D/A converters, so that would explain why the cheap fiber runs make no difference for my purposes.

-Synth80s

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(from http://www.digido.com/portal/pmodule...der_page_id=52)

"Toslink vs. Copper
From: Grant Lyman GrantLyman@mailandnews.com

My comments are:
Bob, thanks for your informative web site and your great comments on the Mastering and Sonic newsgroups. I am hopeful I could get your opinion on a few questions I have. First, have you ever heard Toslink or Glass to sound as good as AES/EBU or SPDIF. My initial tests seem to indicate Toslink and even Glass tend to close the sound stage and thin out the sound. I have heard you mention in the past that the terminations on Toslink and Glass are critical for proper performance. Have you tested what you consider to be properly terminated Toslink or Glass against AES/EBU or SPDIF what was your conclusion.

I thank you, and value your opinion

Grant Lyman
Santa Barbara, CA

Dear Grant:

This is ultimately a jitter question, you know. My answer is that the apparent sonic differences between interface technologies such as Toslink, glass, and copper are IRRELEVANT when doing transfers or when passing signal from one processor to another. You can forget about that question with COMPLETE CONFIDENCE--since all of the technologies are capable of passing perfectly good data, within their specified cable lengths. Remember: the clock is not transferred along with the data. Only the data is transferred to the processor's circuits.

The apparent sonic differences between interface technologies come into play in only ONE place... and that is at the input to the converters (A/D and D/A).

If the D/A is susceptible to jitter on its digital inputs (as most are), then you will hear differences between toslink (plastic fiber), glass fiber, and copper (hard wire). Some D/As reject jitter better than others, and that will determine the extent you can hear these differences. REMEMBER: This is only important to that particular listening session (the D/A only) and not to any other circumstance.

(more)"

30th March 2006	#15
Synth80s Lives for gear Joined: Sep 2004 Location: Beautiful Southern California (cough, choke, honk) Posts: 812	One more thought: I'm using my optical cables to run 16 channels back and forth between a digital mixer and my computer. I think we can all agree that Bob Katz is an authority on all things digital audio -- I'm still reading his excellent book, "Mastering Audio." Bob states that jitter is not introduced over toslink between digital devices because they don't pass clock, but that A/D and D/A connections are the critical paths where digital cable makes a difference. I use word clock all around and Canare S/PDIF to my A/D and D/A converters, so that would explain why the cheap fiber runs make no difference for my purposes. -Synth80s ----- (from http://www.digido.com/portal/pmodule...der_page_id=52) "Toslink vs. Copper From: Grant Lyman GrantLyman@mailandnews.com My comments are: Bob, thanks for your informative web site and your great comments on the Mastering and Sonic newsgroups. I am hopeful I could get your opinion on a few questions I have. First, have you ever heard Toslink or Glass to sound as good as AES/EBU or SPDIF. My initial tests seem to indicate Toslink and even Glass tend to close the sound stage and thin out the sound. I have heard you mention in the past that the terminations on Toslink and Glass are critical for proper performance. Have you tested what you consider to be properly terminated Toslink or Glass against AES/EBU or SPDIF what was your conclusion. I thank you, and value your opinion Grant Lyman Santa Barbara, CA Dear Grant: This is ultimately a jitter question, you know. My answer is that the apparent sonic differences between interface technologies such as Toslink, glass, and copper are IRRELEVANT when doing transfers or when passing signal from one processor to another. You can forget about that question with COMPLETE CONFIDENCE--since all of the technologies are capable of passing perfectly good data, within their specified cable lengths. Remember: the clock is not transferred along with the data. Only the data is transferred to the processor's circuits. The apparent sonic differences between interface technologies come into play in only ONE place... and that is at the input to the converters (A/D and D/A). If the D/A is susceptible to jitter on its digital inputs (as most are), then you will hear differences between toslink (plastic fiber), glass fiber, and copper (hard wire). Some D/As reject jitter better than others, and that will determine the extent you can hear these differences. REMEMBER: This is only important to that particular listening session (the D/A only) and not to any other circumstance. (more)"