what is jitter supposed to sound like?

The Stereophile CD is a good idea. If you want a verbal description from someone who has battled it a bunch, I would say that it makes everything less distinct. It removes the fine details that create depth cues and the quick, high frequency transients that make percussive and plucked instruments sound real and exiting.

Sounds loke something that you have never heard before! If you could hear it, it would sound like a low level hiss.
More important, how would the recording sound without dither? How can one know, since dither is always used as standard.
Bob P.

Opps, I confused 'jitter' with 'dither'! Definitely not the same and of course my comments on 'dither' don't apply here for 'jitter'. My bad!
Bob P.

I think jitter sounds like the jingle of loads of money in audiophile manufacturers pockets for expensive products. The marketeers love the sound of "jittery" and fearful audiophiles who come forth, wallet in hand, with a concern that they have some intractable and immeasurable jitter problem with their system. (immeasurable problems are immeasurably hard and expensive to fix!)

Depending on which "experts" you believe it is either still a problem today or it is something that was caused by poor clock design circuits (or sharing of clocks) in the distant past of digital circuit designs like the early CD.

In theory over sampling is meant to drive jitter problems well outside the audible band where it can be filtered out. Also, accurately clocking things out using a buffer with a dedicated and accurate clock is cheap and is known to minimize jitter.

In theory it can sound pretty much like any other noise or distortion ....as the jitter creates low level frequencies that were not in the original signal. The problem is exacerbatted if jitter is significant and repetitive (as opposed to random) and therefore correlates to a specifc noise signal rather than whiteband noise. This should not normally be the case with most recent designs, even low cost ones.

This is what Bob Katz has to say on what it sounds like;

Here are some audible symptoms of jitter that allow us to determine that one source sounds "better" than another with a reasonable degree of scientific backing:

It is well known that jitter degrades stereo image, separation, depth, ambience, dynamic range.

Therefore, when during a listening comparison, comparing source A versus source B (and both have already been proved to be identical bitwise):

The source which exhibits greater stereo ambience and depth is the "better" one.

The source which exhibits more apparent dynamic range is the "better" one.

The source which is less edgy on the high end (most obvious sonic signature of signal correlated jitter) is the "better" one.

http://www.digido.com/portal/pmodule_id=11/pmdmode=fullscreen/pageadder_page_id=52/

there is some misinformation in one of the posts above:-

>> Depending on which "experts" you believe it is either
>> still a problem today or ....
yes, it still remains a problem today esp. in inexpensive CDPs & DVD players of which there are plenty in the market.

>> it is something that was caused by poor clock design
>> circuits (or sharing of clocks) in the distant past of
>> digital circuit designs like the early CD.
yes, it was caused by poor clock design (one of the reasons was using a high variable xtal for the clock source to keep BOM cost down) in CDPs of yester years. It remains an issue (maybe to a lesser degree) today.

>> In theory over sampling is meant to drive jitter
>> problems well outside the audible band where it can be
>> filtered out.
this is clearly not right! You seemed to be on the correct track citing clock designs & then ........... where did you pull out over-sampling to alleviate jitter?
Over-sampling was introduced to reduce the analog filtering requirements post-DAC.

>> Also, accurately clocking things out using a buffer
>> with a dedicated and accurate clock is cheap....
well not cheap enough for Magnavox ($35 at Walmart) or CyberHome ($38 at BestBuy) to put a highly accurate clock in these DVD player models!
Cheap is a relative term - you'll probably find a good quality clock in some "ES" Sony model & other models costing several 100 dollars. So, yes, if you are one to consider a $600-$1200 DVD or CD player to be cheap, you have a higher probability of being correct.

>> ....as the jitter creates low level frequencies that
>> were not in the original signal.
by low level, I assume you mean "low amplitude"?
Jitter raises the overall noise floor of the instrument thereby masking lower level details.

>> The problem is exacerbatted if jitter is significant
>> and repetitive (as opposed to random)
since we are talking audio here where the jitter issues are almost always clock related, jitter in audio is always repetitive. It is described as periodic jitter or cycle-cycle jitter. It is quantified as RMS jitter or peak-peak jitter.

>> This should not normally be the case with most recent
>> designs, even low cost ones.
How very mistaken are you!!

I personally do not think that there is a "sound" to jitter per se. Maybe there is but I have never heard it. What I've heard is its manifestation: loss of low-level details, reduced D.R. - music loses its snap, imaging not being precise, high freq being edgy/sharp/brittle.