posted 22 February 2002 16:05            

If AES is the source you need to be in sync with, then that the best thing to sync to. The only reason to sync to word clock is when you have a studio with a patch bay and you keep un pluging inputs . In this case you would have to keep changing the sync source every time you repatched. You can't split word clock in the same way as you would with an audio signal, as the clock signal level will be halfed . The source impeadance matches the input impeadance. I always find that syncing to AES or SP/DIF is more relyable anyway.

posted 23 February 2002 06:21            

I have a home setup with a motu 2408 and an alesis QSR sound module with digital output (no signal input).
The text book method of connecting these two would be to let the motu supply word clock to the QSR and then connect the QSR digital to the motu. It simply doesn't sync.I've used every type of cable and it some of which are only two inches long. Of cause MOTU say it's a problem with the Alesis and Alesis say its a problem with the MOTU. I simply make the Alesis the master of the whole studio via digital signal paths, and it works perfectly.

Also we use Audiovision in two of our studios.
Avid supply audiovision digidesign interfaces that use word clock. and they only garentee currect operation if you use the five inch long cable that they supply. And its true . If you use anything else it stops syncing. It seems that word clock is most maufacturers after thought and never realy gets tested fully in all situations, and I suspect that most users end up finding a get round some other way, and it rearly gets reported back as an error to the manufacturer.

If it's dropouts, incompatability and specilized cables that you want, then word clock is the perfect supplier.

If you read a lot of books , word clock seems the right way to go, but in the real world, you learn to avoid it where ever possable.

posted 24 February 2002 18:02            

BTW, I just switched from StudioVision to Performer and from a G3 300 to G4 733. I can hardly contain myself. Really looking forward to that ASIO integration.

posted 27 February 2002 20:59            

Your generalisations are all wrong. Most pro equipment has very good wordclock implementations and this is the way to sync digital equipment to avoid possible framing errors (I think Yamaha called it in the past 'bit shift'). AES/EBU implementations can work for a few connections and in fact I use it too if nothing else is possible. But if you have a somewhat larger setup you're forced to construct a mess with daisy chained AES/EBU (or even S/PDIF) connections. This can produce timing errors between digital devices thru different cable lengths. Some devices can produce digital feedbacks therefore you have to use 'black frames' for syncing. All this adds up to a technical and ergonomical mess that is elegantly solved with wordclock connections via WC distribution amps. As the wordclock master I would suggest the DA converter you listen to. The technical details are better explained by the mastering engineer Bob Katz. My technical knowledge is limited in comparison.
Another advantage with distributed wordclock is that you can switch off and on your devices without disturbing your digital setup by accidently shutting down an AES/EBU device you need for syncing.
Wordclock is not to be avoided, as you stated, but instead the prefered, superior solution. This is based on 'real world' experiences.

Nirto Karsten Fischer

posted 28 February 2002 09:09            

Pete