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Femto clocks ,every unit should have one

I was reading in Computer Audiophile even the .$400 Geek pulshas a a Femto clock. It is inexcusable for any credible company to not consider a Femto clock they are 1,000s of times more accurate then a a Pico master clock. We are speaking of a a Trillion times ,vs millions.
More accuracy ,equals less jitter more refined ,better resolution.
These clocks were several $1,000s a few years ago . Now a .085 Femto clock maybe $50 and made in the U.S.A the Geek puke use this.
I bought so Wyred SE dac then realized it has far superior low distortion parts but over looked a major part,the new kid in the block the Femto clock.i have been asking them to upgrade this dac most far no response ?
Why .they still have a lot of old pico clocks they want to off.
If buying any new dac a Demand a a Pico clock.BTW the vega dacs parts are not as close tolerance as the wyred SE dac,but it does have a Femto clock. Wyred needs now to step up to the plate .it sounds very good
It could be that much better with this clock.
audioman58

Showing 2 responses by larsclausen

larsclausen
2 posts
 
The term Femto clock is actually a registered trademark for IDT for a MEMS type oscillator, but i suspect this is not what we are talking about here. W4S are talking about Femto grade clock. I contemplate they are referring to jitter performance in the femtosecond range. Did anybody check out if this jitter is specified for the Audio range, or the industry standard 'Sonet range' of 12 kHz - 20 MHz? (In which case the low jitter spec is pretty much useless).
larsclausen
2 posts
 
I agree with most of what Wisnon just said. I wouldn't claim that every chinese CPU clock can beat any femtosecond clock, but maybe some of them.
These canned clock's are usually made with a logic gate as the active element, in a Pierce coupling. Such as the 74HCU04 The equivalent input noise is relatively high. I don't think anyone would use 74HCU04 as a RIAA amplifier?
Noise on the input of the active gate, transfers directly to jitter in the clock signal.
Also the input level is half that of the Vsupply. So half of the noise on the supply rail is transferred to the input. That's why the regulator is of great importance.
Much better is the Colpitts oscillator, built with discrete transistors. Here you can get somewhat better noise (jitter) performance.
I agree with Wisnon also that jitter is not necessarily a make or break factor, the problem is when the music signal is transferred to the clock, over the 5V supply lines. That is going to kill depth perspective, and sound stage. And strangely if you have a jitter instrument, you will find this in many CD players or DAC's. Random jitter is far less intrusive, and like low order distortion in tube amplifiers, it can mask other distortion / jitter.
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