There is no way out of the box to apply an external clock sync to the
touch, you have to apply some form of surgery. 

The easiest way is to replace one or both of the "audio" crystals with
a clock from the outside world. The touch has two crystals: 22.5792 MHz
for 44.1 and 88.2 and 24.576 MHz for 48 and 96. 

You need a clock source that supplies these frequencies (if you build
your own its easy, finding a commercial one that does this is going to
be real hard). If you want to use a real wordclock you will need a
frequency multiplier to take wordclock up to one of those two
frequencies. 

If you want to be able to change the sample rate on the wordclock you
be better off injecting the clock after the clock mux in the touch. 

You COULD implement a sync through S/PDIF with a S/PDIF receiver
appropriately configured. Many of these can be setup to output the above
clock frequencies. 

I have personally done the external clock replacing the crystals
approach, it works very well. Of course I build my own DACs so I can use
whatever frequencies I want. One nice advantage of this is the touch can
now use its normal sample rate switching mechanism. I have the DAC
reading the optical S/PDIF out from the DAC, it decodes the stream and
figures out what sample rate is being used and automatically sets the
DAC to use the right local clock. So you get the advantage of local
clocks in the DAC with the source synced to those clocks AND the source
can do its normal automatic sample rate switching.

But it does take simple surgery of the touch.

John S.


-- 
JohnSwenson
------------------------------------------------------------------------
JohnSwenson's Profile: http://forums.slimdevices.com/member.php?userid=5974
View this thread: http://forums.slimdevices.com/showthread.php?t=74585

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

Reply via email to