Digital Facts and realities?

[AJSki2fly]

Some might find this an interesting and informative read CD: Jitter, Errors and Magic

It gives and insight into some technical issues with CD and digital storage, most of us will have ripped CD’s to hard drives or some other form of storage and/or will be listening to CD’s so the issue discussed will be relavent and may even be with streaming.

[Macca]

? What jitter are you talking about?

Periodic jitter.

[Light Dependant Resistor]

Not so sure about jitter. Jitter sounds like tape wow and flutter. We've all owned or heard a cheap cassette deck (except maybe the youngsters) so we all know what that sounds like. The wobble on sustained notes. Who's ever heard a digital source sound like that? (unless it's actually on the recording like on the Boston album 'Third Stage' for example).


Even that cheapo DVD player you found in a skip has better jitter performance than any RTR deck or turntable by quite a large margin. There needs to be a lot of jitter before it is possible to hear it. http://www.ultrahighendreview.com/up..._on_Jitter.pdf

I would accept the findings of this article with less respect than talking to your local politician.
"Jitter induced by the digital audio interface was not found to be an audible problem for any of the program material auditioned"

Where is explanation of any circuitry different to SPDIF ... not in the article.. so how can they possibly affirm anything different as being audible to SPDIF ?
I explored this very area in 1997 http://www.enjoythemusic.com/magazin...iesofspdif.htm and finding ridding your digital transfer of SPDIF
makes considerable difference - audible as better bass response and stereo separation.

With CD players as a segment of the digital replay devices, there is greater reward in finding the right op amp for the current to voltage analog output stage.
As example Sony CDP555ES benefits enormously from using 6x opa2107 . A marantz CD52SE mk2 the op amp to use is 2x LM4562

[Macca]

I would accept the findings of this article with less respect than talking to your local politician.
"Jitter induced by the digital audio interface was not found to be an audible problem for any of the program material auditioned"

Where is explanation of any circuitry different to SPDIF ... not in the article.. so how can they possibly affirm anything different as being audible to SPDIF ?
I explored this very area in 1997 http://www.enjoythemusic.com/magazin...iesofspdif.htm and finding ridding your digital transfer of SPDIF
makes considerable difference - audible as better bass response and stereo separation.

It's not an article its a study. With proper controls etc. There's no problem with Sp/dif that we can hear. That's really the funny thing, digital replay may not be perfect but it is way better than our hearing requires. and way more perfect than the alternatives of analogue tape or vinyl. Fact is we can tolerate large amounts of distortion or jitter before we start to notice them. If we couldn't no-one would ever play a vinyl LP again. And that's before you even get to the loudspeakers, A small loudspeaker can have 10% distortion in bass frequencies, no-one seems to mind. But 0.001% distortion from a CD and everyone is running around looking for a solution.


I think a lot of people underestimate just how much manufacturers will happily lie to us in order to get our coin. Even the big boys like Sony.

[Yomanze]

Good explanation of the different types of jitter here: https://ransomsnotes.com/index_htm_f...heAcronyms.pdf

[Macca]

Jitter was a solved problem before CD even came out. I've got vintage players here that will demonstrate that on a practical level. (Marantz CD54 from 1984, Technics SLP1200 from 1989).

The SQ issues people experience with CD have nothing to do with jitter.

[Yomanze]

Ever tried adding a better clock?

The SQ improvements I’ve heard in my system, with a DAC I’ve used for 7yrs, just from a lower jitter signal, is blatantly clear.

It uses a simple SPDIF receiver with a PLL that isn’t doing anything much, so is very transport sensitive...

[Jimbo]

Jitter was a solved problem before CD even came out. I've got vintage players here that will demonstrate that on a practical level. (Marantz CD54 from 1984, Technics SLP1200 from 1989).

The SQ issues people experience with CD have nothing to do with jitter.

What are the SQ problems associated with CD if we exclude jitter?

[Macca]

What exactly is a 'better clock' though? And how are you certain that the improvement you hear after the modifications is due to reduced jitter and not some other factor? Now I'm not saying it couldn't be but for there to be an audible improvement the levels of jitter before the mod would need to be extraordinarily high. Possible but very unlikely. What is the DAC?

[NRG]

Periodic jitter.

Ok but how does periodic jitter manifests itself as sounding like tape wow & flutter