Yes, sorry, I was being lazy. 
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Well in the case of the Esoteric, it’s a master clack generator, not a variable word clock. All outputs are fixed 100 Mhz
It sounds more like a 10 MHz frequency reference rather than a clock generator. I suspect you can then add another box which generates the word clock at the appropriate frequency. Not cheap and whether it’s strictly necessary…
For Esoteric, no. Just the 10 Mhz master clock. I’m not aware of any support for word clocks on any of their transports. They all take a 10 Mhz in.
They are certified atomic clocks though. They have an internal enclosure for the isotope and sensor. It’s both nonsense and very cool all at the same time.
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It’s almost seems like a product for those that have run out of things to buy for their system, it seems kind of pathetic in an odd way.
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A bit harsh. There are plenty of comments/reviews out there that give very positive reactions to adding an external clock. Just, if I may say so, are similar comments re. adding things like external/additional power supplies or, for example, lan cables costing hundreds of pounds per metre. I think such judgements can only be passed after some proper listening tests.
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Indeed, most professional periodic clock references I know are 10 MHz and some also 100 kHz as well.
We also use time clock references, called Stratum 1 master time servers typically linked to Stratum 0 atomic clocks … but I am not sure they would help digital audio replay 
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Lots of people say that about external power supplies.
Different designs attack different problems in different ways. I agree that integrating a transport and DAC into a single box should nullify many of these clock issues, but by most accounts, Esoteric sources are pretty special. I’ve not heard it so I can’t knock it.
Why should integrating a transport from the DAC nullify the clock issues? I think can cause significant challenges that need managing.
It’s the DAC that creates the clock for the transport streams that are sent to it, not the transport. Sure in the limit an ultra low frequency (0.1Hz etc) feedback can be used to adjust the transport rate … but without that it hardly matters… there be a sample slip in every 30 to 60 minutes which is hardly going to be noticeable and indeed I don’t.
The major benefit is decoupling the transport from the DAC and its clock for increased stability irrespective of any sort of perturbation from the transport itself, which is typically operating in a noisier environment than the DAC.
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On carefully designed devices, it can be simpler to share a clock between sending and receiving endpoints. Good or bad as the clock is, they both can take the same master clock without the complications of an offboard DAC, 2 clocks and whatever other complications arise.
I believe Naim are a big proponent of combined transport/DAC CD players largely because they felt the problems solved by putting them together with a common clock and a fully engineered bridge between the two outweighed the benefits of the seperate transport DAC model with the different complications that model brings.
That’s not to say that’s the correct approach. Different brands attack problems differently to play to their engineering strengths and avoid their weaknesses.
They are indeed… but if you look at the hundreds and hundreds of posts about Ethernet leads, switches, fibre media converters etc… it does suggest there might be a more efficient approach… by decoupling transport from DAC I have none of these SQ variabilities now, my home network is immaterial as long as it functions, it’s more about responsiveness now … but each to their own.
Back onto clocks…
So I was reading the excellent article at stereophile https://www.stereophile.com/reference/1290jitter/index.html and I’m pretty sure I mostly understand how it effects the sound. However can anyone say how the perceived audible effect will vary on the sample rate frequency? It would seem, to me, that a jitter on a 44.1KHz stream would be more audible than on a 96K stream since the affected proportion of the sound wave would be larger at the lower sample rate. Also a jitter on a note would be more pronounced on a higher frequency note than on a lower.
Yes?
Are they not referring at the external clock input on the Grandioso external clock from esoteric? There it is possible to add an militaire GPS based clock with an 10mhz output.
blimey such expensive clocks - the price of rolex?
Nope. The Japanese site shows the isotope enclosure and specifies the isitope and particle rate it emits. Rubidium is used as in many atomic clocks.
Maybe you can explaine this:
A 10 MHz or 1 pps reference signal can also be input externally by connecting a device such as a GPS receiver to an external input terminal. The internal rubidium oscillator is synchronized with a higher center frequency precision clock received from a satellite, and this allows more stable rubidium oscillation than the crystal controlled oscillator built into the external GPS receiver, which makes the most of the advantages of a high precision GPS system.
Err if you want to untangle that, I’d suggest firing off an email to TEAC support.
There is even an review on the internet from some reviewer that connected his gps clock to the esoteric.
That article is addressing what DAC clock jitter does to reconstruction. This is why most manufacturers like Naim, Chord etc of DACs pay very close attention to the clock and signal integrity of the clock.
Where I come from using an external clock unless synchronisation with multiple devices is required in a recording studio for example will add challenges to clock signal integrity.
In days gone by highly stable clocks were bulky affairs and were often separate. Modern methods and electronics makes that unnecessary (unless for multiple device synchronisation) and allows the benefits of locally providing clocks reducing the clock signal path in audio DACs.
Obviously one can use the old fashioned way if required, but unlikely to be any benefit and more likelihood for detrimental affect with modern DACs.
Also whilst we are talking of DAC jitter, don’t forget ADC jitter. This is outside of our control and it’s footprint is encoded into the digital signal. However we can reduce the noise power from it by oversampling on the DAC reconstruction.
I love the DSP mathematics on this aspect, it’s so neat… and can be a real benefit of accurately oversampling. This means the higher DAC clocking multiples must be highly stable. Again this becomes easier to achieve in highly stable combined clock DAC designs, again from the like of Naim and Chord amongst many others.
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I don’t know what you’re inferring.