P Floding;153270 Wrote: 
> I believe most people stay away from Toslink due to it's measured jitter
> performance. Doing so, of course, may be a mistake.

You seem to have entirely missed the point - these DACs are independent
of the transport jitter.

Robin Bowes Wrote: 
> 
> Adjusting the clocking of a digital signal will not produce frequency
> distortion related to the periodicty of the change, i.e. making a
> change
> every 2 seconds does not imply that only frequencies below 1Hz will be
> affect.
> 
> A change in the relationship between bits in a digital stream is much
> more likely to cause artifacts at higher frequencies.

It _will_ produce distortion at the periodicity of the change, although
you're correct that it will also affect higher frequencies, in principle
(it can create sidebands, which will be shifted a tiny amount away from
the original tone). 

But think for a minute about what this does - every 10 seconds, the
frequency of the DAC clock changes by a very small fraction.  So every
10 seconds the absolute key (or whatever it's called - the frequency
corresponding to middle C) of the music shifts by a tiny, tiny amount.

Unless you have perfect pitch the absolute key is irrelevant anyway. 
Here the change is really small - it depends on the difference in rates
between the DAC clock and the transport clock.  So there will some
minute shift in the key of music which remains constant for ten
seconds, then shifts, remains consant again for ten seconds, shifts,
etc.

So it's true that the Fourier transform of that entire sequence has
high frequency components which have been shifted, but that's
irrelevant to what you hear - what matters is the FT over much shorter
time scales, and in any case the sidebands will be so close as to be on
top of even a very pure tone.

Even if you think this is bad for somer reason, it's got nothing to do
with tranport jitter - a DAC designed this way is totally immune to
that.


-- 
opaqueice
------------------------------------------------------------------------
opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234
View this thread: http://forums.slimdevices.com/showthread.php?t=29450

_______________________________________________
audiophiles mailing list
[email protected]
http://lists.slimdevices.com/lists/listinfo/audiophiles

Reply via email to