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Prima Lunacy? (SuperTubeClock)

I am planning on upgrading my tube amp when its current set of tubes start to go.  So I've been doing a bit of perusing online, and was really considering the Prima Luna integrated amps until I read about "the world's first tube-based data clocking device: the SuperTubeClock™"

Did I missing something or is this just about the most obvious snake oil sales job?  For what I am understand the Prima Luna Engineers are using a tube-based oscillator in lieu of a quartz crystal to generate the DAC chip clock signal.  Their blurb lists reduced jitter and noise as the advantages.  AFAIK the noise in a timing signal should be superfluous since it has two values 1 and 0, and anything in between (noise) is ignored.  If the clock signal "noise" is leaking into the final analog output, then there are big problems with the DAC chip.  With respect to jitter, I would expect the inaccuracies of a high-quality crystal oscillator to be measurable only in the nanosecond or picosecond range.  Can an analog-style oscillator really do better (and does it really matter)?

Another thing that stuck me is that the clock triode is soldered in, and there is mention of it lasting 5 - 10 years.  When it goes bad, do owners have to send their DACs to Prima Luna to be refitted with new - and possibly rare and otherwise unavailable - clock tubes?

Thoughts, anyone?
tinskip

Showing 2 responses by tinskip

tinskip OP
2 posts
 
Almarg, thank you for your response, but I still remain completely unconvinced about the value of the SuperTubeClock for the following reasons:

(1) I have never heard of another case where an analogue-type oscillator was deemed more precise than a quartz crystal oscillator. Analog oscillators are subject to some degree of thermal drift.

(2) In the PrimaLuna page there are nice scope images for the output of the SuperTubeClock at two frequencies, but they are not being compared to anything. Why do they not show the output of a high-quality crystal clock?

(3) Even if the SuperTubeClock were indeed more precise / less noisy than a crystal oscillator, then the clock of the ADC which captured source audio signal would have to use one as well for the SuperClock-timed DAC to have much value. If both the ADC and DAC clocks have jitter in some situations the "jitters" may cancel each other out!  But then they could add up as well, I guess.

tinskip OP
2 posts
 
I just read PrimaLuna's page for their EVO 400 amp, and according to it, at the very bottom "OUR AMPS ARE PERFECT. BUT YOUR SYSTEM MAY NOT BE", they are the only ones who know how to make use of EL34's, and their amps are so awesome they can make up for crappy speakers.  Wow!  These guys really are full of it!

I guess I'll be looking elsewhere.  I have time.

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