Motu Suck. Reason #1

[Martin Naef]

James R. Coplin wrote:
> Since we are talking word clock, I've always had a nagging question.  I
> mainly use AES and S/PDIF for interfacing with my outboard.  Since both of
> these signals provide clock, is there any reason to also use wordclock?

If you use digital processors (digital in, digital out), there's no 
advantage at all (unless you have transmission problems). If you 
synchronise converter boxes, there could be an advantage in terms of 
decreased jitter, as the box does not need to derive the sync from a 
modulated signal. If you use a crappy digital cable, the derived clock 
might include a bit of jitter due to the "smeared" signal without 
clearly distinguishable edges.

Now whether that theoretical advantage translates into an audible 
difference, I don't know. I'd expect any reasonably modern piece of kit 
to use decent quality PLLs to generate a low jitter internal clock. And 
if you use decent quality digital cables, there shouldn't be more 
"smearing" than on the word clock cable.

Personally, I use word clock to sync those devices that have no other 
option: A Korg Trinity and a Z1, each with ADAT out but no digital in.

I'd take the reports where adding a word clock suddenly improved 
everything massively with a grain of salt. Either, this is somebody with 
golden ears and the gear to match it, or their system previously had 
some cabling issues or a really poor original clock source. If the 
digital connections were borderline reliable, adding the clock might 
have resolved these issues.

> I've never had a problem with dropout and everything sounds fine.  Are the
> clocks actually all synced in this type of setup or just "close"?   Should I
> also implement the wordclock network?

I'm sure you could borrow a bunch of video cables and test it. I'd be 
curious to hear about the results. But for my system, I think I'd start 
optimising somewhere else before I become anal about clocking...

Martin