Esoteric K-01

While it does not reduce jitter, a good external clock can have some benefit, depending upon how resolving your system is and what the internal clock is doing. I have heard my system sound better with the external clock in it using my UX-1, but that's before the player has the benefit of Alex's clocking. I don't think I'll ever know whether an external clock would improve Alex's internal clocking because I doubt that he'll ever build a piece that would take an external clock.

I'm pretty much out of my league technically to explain this any further - I don't know WHY the external clock made things sound better, it just did. It was most noticed when I turned the external clock off - some of the airiness seemed to be missing. I'm sure Mr. Harley can explain this much better than I.

Matjet,

I tried posting a response but it looks like it was not up to moderator's liking, and probably for a good reason.

Anyway, here is a summary of what I think:

1. Esoteric digital is synchronous so it benefits from external clock for the sake of synchronization between multiple clocks used, even in the single-box players. If you are trying to justify external clock for your K-01, I am sure you will be happy, so go for it.

2. APL Hi-Fi digital is asynchronous so there is no benefit from using external clock, even if it is Atomic.

3. To my knowledge, clock stability has nothing to do with clock jitter. For example a clock rated at 25ppm will result in 0.0025% speed stability. Clock rated at 1ppm will result in 0.0001% speed stability. In both cases, this is something you cannot hear and in both cases the clock jitter performance (short term stability) remains the same.

Best wishes,
Alex Peychev

Hi Alex,

I appreciate your response. However, I am still confused.

If a more accurate external word clock does not reduce jitter, how does it improve sound in a single box CD/SACD player that has only one master internal word clock? Synchronization by an external clock would be unnecessary since there is only one clock. The unit's transport is 'slaved' to the internal clock which connects with the DAC. The transport and the DAC are already synchronized by the single internal word clock.

According to what I have read (at least the way I understand it), it is inaccurate timing and/or timing errors that lead to clock jitter. A more accurate and more stable word clock, provides more accurate timing and fewer timing errors. The result is significantly less jitter resulting in improved sonics.
Is this not an accurate statemnt? Please explain.

Could you explain the difference between asynchronous and synchronous digital in layman terms and tell why you feel asynchronous digital is better than synchronous?

Thanks again

Hello Matjet,

Different engineers like to take different design approaches, the ones they believe are best for their equipment. This said, I cannot further elaborate on why external Esoteric clocks improve the sound of their digital audio equipment without getting into technical details which may be a conflict of interests and against the non-disclosure agreement we have signed. Maybe it is a good idea to contact Esoteric and ask them to provide an explanation that will help you better understand the benefits of their external clocking when used with their digital audio players and systems.

I have chosen asynchronous because it brings better results with my design approach.

If you are indeed interested auditioning the NWO-M and evaluating its performance, we can arrange it. Otherwise, there is no point trying to prove what we think is better or not from a technical point of view. After all, the audio quality achieved is the most important aspect, and I am sure that it will take you about 30 seconds to determine the NWO-M performance level. Of course, it is not at all fair comparing production equipment with an all-hand-made boutique. This is the reason why Esoteric and APL Hi-Fi do not really look at each other as competitors. Hope you’d understand!

Best wishes,
Alex Peychev

And the sell-a-thon continues from whichever continent apl is currently based.

Subject to change of course.

Maybe tomorrow.

Or Tuesday.