Opinions on Esoteric clocks ......

.....I have read the previous threads on these pieces, and would like to hear from people who have bought them as well as the ones who did not and why. I understand what it is doing - just wondering if the sonic improvements are worth the money.
Antelope clocks are better and value for money.
....never heard of them. Show me the way
Search for Antelope Audio. They appear to be pro audio.
I have a G-OS Rubidium clock and have had it about 1 1/2 yrs. When I turn mine off, it feels like I'm losing a bit of musicality and detail. As far as whether it is "worth it", it will obviously depend on the rest of your system and what you are trying to achieve. You might or might not hear a significant difference - the only way to tell is to demo one.

I am the second owner of mine, so it had already been "broken in" before I got it. Esoteric also supports their gear exceptionally well, which I have come to greatly appreciate. Good luck!
.....I currently own the Esoteric P-05, D-05 combo...so the clock would be used with them
Which clock? The Esoteric Rubidium clocks will have more of an effect than their lower-end clocks in a highly resolving system.
......The Rubidium is out of my price range - the one that is is their G03X.
All you can do is try it and see....
I have added the GOR-b between the P-03 and D-03 after more than a year using the two alone. It is really hard to say what, specifically, it does, except that when you remove it the naturalness of the sound is diminished, and even superb CDs and SACDs become excellent digital sound again, not just excellent sound. I have heard from a very reliable source that the G03x has little positive effect between the P-03 and D-03, but is a substantial step forward when used with the P-05 and D-05. If, after my own experience, I were going to get a P-05/D-05 combo for a second system, I wouldn't even consider it without an Esoteric clock, the best I could afford.
I'm in the same boat, I have a D-05 and trying to determine which clock to purchase. Here are some numbers I found researching;

Clock accuracies in ppm:
Internal Esoteric D-03 = .5 ppm
Internal Esoteric D-05 = 3 ppm

Esoteric G-03x = .1 ppm = $4,000
Esoteric G-0Rb = .00005 ppm = $15,000
Antelope Isochrone OCX = .02 ppm = $1,495
Antelope Isochrone Trinity = .001 ppm = $4,750
add Antelope Isochrone 10M to the OCX or Trinity = .00003ppm = add $6,495 to either clock

Prices are MSRP

If it's all about ppm and $$$'s, I was considering the Isochrone OCX, but if power supply etc.. play a major role maybe the G-03x.

Excuse my ingnorance

Is possile to use this antelope isochrone 10 m with dcs puccini? or with esoteric X01 D2? has someone experineced before? I nave heard about them

If you will allow me, I’d like to elaborate on the external clocks use.

Something that should be realized about using a "super-precision clock" is that the stability of the clock in ppm (parts per million) does not have anything to do with improving short term instabilities, also known as clock jitter; all it affects is playback speed stability. In other words, if there is a deviation (plus or minus) of the clock frequency, you will hear increased or decreased playback speed, nothing else. Let’s say the audio master clock is 22,000,000Hz (or 22MHz) specified at the “extremely high” +/-100ppm frequency deviation, then you do the math what percentage is 100 parts per million from this frequency and you will find out what will be the speed deviation. Simply, this is something you cannot hear and hardly measure.

When it comes to digital audio, the jitter (or “period jitter”) is what’s important for best sound quality, not the frequency deviation/stability, which is negligible even at 100ppm.

External clocks are made for synchronization of multiple digital audio/video devices in studios and TV stations. The external clock is usually converted to DC voltage that controls a VCO (voltage controlled oscillator). While this synchronizes everything connected to the “house clock” (the external clock) and locks the frequency, it has nothing to do with clock jitter. Not to talk about the fact that, usually, the VCO is used as a reference to a multi-clock generator that is PLL based, so the jitter can sometimes exceed 400pS, although the frequency deviation is locked to some really low figure as 0.00005ppm. Compare to a non-PLL clock oscillator with 2pS of jitter, although its frequency deviation is specified at 50ppm or more.

Hope this helps you understand digital audio clocking even better!

Best wishes,

Alex Peychev
Dear Alex,

Well said! I hope you are doing well in all your endeavours!

Best Regards,

Kyle Takenaga
I have a P5/D5 with a Gorb clock. The Gorb clock makes the sound more clear and focused without being bright at all. The improvement was worth the money for me.
Bugman03, I've heard this improvement myself with Esoteric's P01 and pair of D01 DACs in their room at CES.

When it comes to synchronous digital audio components (such as Esoteric are), it is beneficial to have external clock because it "locks" them all to the exact same clock frequency. For example, your P05 has a VCO used to reference the PLL multi clock generator, and the D05 also has a similar clocking architecture with another VCO. The two VCOs (one in transport, one in DAC) are impossible to work at the exact same frequency, unless they are "locked" to an external reference (the external clock). This is why the sound is more focused with the external clock. Furthermore, if there was a clock output from your P05 so you can feed D05 with it, you wouldn’t need external clock because the benefit would be the same.

Above does not apply to a single digital audio component (CD/SACD player) simply because there is no benefit from an external clock, IMO. It also does not apply to a Transport/DAC combination where the DAC is asynchronous.

Alex Peychev
So, the clocks do not help with jitter....they merely put the two players ( transport and DAC ) in sync. which improves the overall focus. Right ?????
Hello Garebear,

Correct, the external clock cannot improve the jitter of the internal clocks; it locks them to the same reference frequency.

I understand that frequency stability/deviation specification of external clocks is extremely tight (this is why they are so expensive) and there is benefit using them with multiple synchronous digital audio components, but that has nothing to do with improving the short-term stability/jitter of the internal clocks, which is critical for optimal D/A conversion.

Alex Peychev
Technically, this is all pretty much over my head. All I can comment on is what I hear. So I have to take issue with the comment above that "if there was a clock output from your P05 so you can feed D05 with it, you wouldn't need external clock because the benefit would be the same." Unless I misunderstand, this seems to be saying that if you can slave the transport's clock to the clock in the DAC, the result will be the same as with the external clock. (If I misunderstood, sorry.) When I ran the P03 and D03 by themselves, of course the P03 was slaved to the D03's clock. The very substantial improvement when the GOR-b was added was over the P03 slaved to the D03.
......and let's not forget - ahhhhh - the cost of 2 BNC cables - and the cost of another power cord which from what I have been told does make a difference on these clocks. My system is witred with Purist Audio 20th Anniversary's ...not cheap !