The explanations below may seem too simplified and perhaps elementary to advanced members here, yet I feel they could be of interest to those still wondering what all that JH3A fuss is about, so please bear with me.
Qusp, I think your mental constructs related to jitter are valid, yet you perhaps need a little leap of faith to emotionally accept a slightly different reality. When you say
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the ONLY clocking method (not reclocking) able to eliminate jitter in the playback mechanism, is to slave the transport clock to the dac clock, have them be one and the same, but then you also have the issue that the clock used to create the digital data in the ADC is different lol", you are hitting the nail right on the head - I believe that's exactly what's happening inside JH3A, and IMHO it is wonderful.
Only instead of an external transport, the slaved transport is a RAM buffer (or several logical buffers) that the DSP operates upon. In order to filter/split signal in the frequency domain, the filter/splitter has to have memory for signal samples. Details of algorithms vary, yet fundamentally in order to figure out the component frequencies of a signal (or even the frequency of a single pure sine wave), it has to be observed over time.
In case of old school passive filters, the capacitors and/or inductive coils in combination with resistors play the role of that memory. Such filter is not perfect though, as it doesn't remember the whole signal over a period long enough to perfectly recognize its shape but rather stores the signal's averaged secondary characteristics. The more memory elements (capacitors and coils) are added, the more precise the filtering/splitting becomes. Unfortunately, adding more elements also results in the degradation of signal, both in terms of amplitude and phase, as well as makes the filter/splitters heavier and more expensive.
Filtering/splitting/adjusting in digital domain opens up entirely new opportunities, as the number of memory elements can be measured in hundreds and thousands instead of single digits. With a RAM buffer of sufficient width and depth and quick enough processor, the signal can be split onto numerous frequency ranges with great precision, selectively attenuated, phase shifted, and then brought back to the amplitude domain - again with great precision - so that when the sound waves emitted by several transducers arrive to a listener's ear drum, their superposition results in the patterns of air pressure very close to the ones generated by live music experience.
Several transducers are needed because we usually want each one work in a "smooth" area of its frequency response curve, far enough away from its natural mechanical resonance frequency, where it could produce wild uncontrollable spikes, yet also far enough away from its "running out of steam" too low or too high frequency. This principle is not universal - some transducers, especially those used in subwoofers and cheap boom-boxes, work very close to their resonance so that their efficiency can be higher.
Somewhat unfortunately for humans, a typical mechanical transducer can usually cover about one third of the useful frequency range (expressed logarithmically), so we need to use three or four of them. One would be just enough for birds, who can only hear up to 4KHz, and we'd have hard time keeping up with the dolphins, who as I recall can hear sounds up to 200KHz.
One transducer in a typical dynamic full-size headphone, which seemingly disproves what I just said, is a curious case. First of all, it does in fact combine several transducers in one as its flexible membrane participates in several modes of motion - slow whole surface back and force motion for low frequencies and quick waves running from the center across the membrane for high frequencies. Secondly, the resulting frequency response curve is far from ideal - even the best full-size headphones may have several peaks and valleys of up to 9 db across the useful spectrum and also typically introduce significant phase incoherencies, while a four-way professional monitor can be flat at +- 1.5 db from 16 Hz to 32KHz with near-zero phase incoherencies on its focal axis.
What JH is doing is applying proven design principles, heretofore only fully developed for high-end professional monitors and super-expensive exotic loudspeakers (== professional monitors wrapped in nice veneer), to relatively "affordable" headphones. An additional advantage is that the headphones in question are individually fitted in-ears, which provides well-controlled geometry and excellent transduction efficiency. In case of professional monitors, no matter how good they are, one needs to have his or her head in their focal point to fully enjoy the experience.
The members who listened to the JH16/JH3A combo describe an experience similar to the one I typically have while being in a focal point of my system, which comprises mostly of professional monitors driven by a digital processor . A practical joke I like to play on people who visit our home for the first time is asking a person to sit on the focal seat and then turn on something like Kitaro's Sacred Journey of Ku-Kai in its whole 5.1-channels SACD glory. After five or so seconds, the person's eyes invariably widen and jaw drops - the "teleportation" effect is that strong
I have to say though that certain CDs and even some SACDs are becoming painful to listen to with such a good system. Not only rampant dynamic range compression and frequency atrocities, but localization errors are becoming glaringly obvious (one of my "favorites" is a track made in Russia where lead vocalist appears to be situated straight behind a gitarist and the vocalist's head appears to be bigger than the whole gitarist's body - makes for a very weird impression, or maybe it was an underpaid mixing engineer joke
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The difference between 16/44 and 24/96 becomes clear as night and day with such an accurate system. That's the reason I'm voting so hard to bring a reliable easy to use on the go 24/96 interface to the JH3A. Believe me, you'll develop cravings for wide-high-bit-rate recordings. Better have a system that can easily satisfy them for years to come!
There is a synergy similar to the one existing between Blu-ray disk and full HD TV - one needs the other to fully realize its potential. In JH16/JH3A combo, you'll have an analog of the full HD TV. Just like watching old DVDs became a bit less exiting after introduction of Blu-ray, listening to 16/44 on a system with such high audio resolution will become a bit less exiting as well.
I hope this long treatise will be helpful to some of you. I only try to return a favor, as I'm learning so much from this forum. Have a nice day!
EDITED for typos and emphasis.
