Jitter

[richidoo]

A nice jamboree about jitter

http://www.computeraudiophile.com/content/Some-additional-thoughts-about-measuring-jitter

[Deton Nation]

interesting read.
Thnx.
Mike

[tmazz]

I had an experience a few years back that  completely blew my mind with respect to the importance of timing in digital audio. The members of the AudioSyndrome were invited to the home of Gene Pope  (of PopeMusic records) to listen to his system (all Cello) and to some of the original master tape of his recent CD releases. Gene was (is) a timing fanatic. All of his recordings were done direct to two track,on Nagra digital recorders using external high precision timing sources every time the tapes were play in the production process they were played back using not only the same model external clock, but the same unit that was used as the timing source in the original session. (He actually had a hard time finding a mastering lab that had equipment that would allow him to bring in his clock for them to use.) He played us one of his tapes (a first generation original master tape being played on a system that cost more than my house) and the sound was absolutely glorious. Then he flipped a switch on the back of the Nagra that switched from the external to the internal clock in the Nagra itself. WTF!!!! Everything collapsed closed up and started to sound artificial, or just more like a CD. According to Gene, it was not the fact that the Nagra clock was that much "worse" that the external unit, it was just that it was different.

So never underestimate the value of a clean timing signal in your digital system. Outside of the 44.1K/16 bit sampling standard (which we can't do anything about) it is really the Achilles Heel of the digital audio chain. Anything we can do to improve it (either through better internal designs or external devices) will pay us back in spades.

[richidoo]

Lots of new CD players and DACs coming this year full of new jitter killing methods. I think this is the year jitter takes its last gasp in the buget audiophile system. BelCanto, Eastern Electric, Sim, probably some others too, have new reasonably priced DACs which should eliminate jitter.

It sure does make a huge difference. The ESS dacs are great for clarity and focus like you mentioned Tom, even with known crap transport. I think it's because of the jitter killing system it has, but it does reference an external crystal. Wonder if it would be even better with a super clock.

[Lizard_king]

Use a computer setup that is proper with the Hi-Face BNC and use a great SPDIF BNC cable. Jitter is so low your sound stand grows!

[rollo]

There is a more to it than jitter. spurious high frequency noise, RF and phase abnormalities. Actually measurements prove that some SPDIF connections have less jitter than USB. However cannot be discerned as the measurements do Not correlate to the sound heard. Jitter is a "catch" word of the day IMO. jitter has some affect as evidenced but then again some DACs with higher jitter sounded better than ones with lower jitter, go figure. Computers actually degrade the signal internally from EMI and RFI contamination and jitter measuring over 1000 at the source[ computer]. Poor power supplies as well..  It takes a lot more than controlling jitter for good digital sound. I say phase shifts and noise above 20,000 HZ is more of an issue. Limited by the DAC chosen as well as the manf. of such dictates how jitter is affected.
  The argument is similar to distortion figures. SET anyone ? Sansui anyone ? The bottom line is that jitter reduction or addition does NOT warrant good sound. They just have not learned all there is to learn yet. I'll wait it out.



charles