no sound + noise problem with adat exb-i interface

Zult! · Post by **Zult!** » Sun Oct 09, 2011 11:59 am

hello everybody
I have a problem connecting my Oasys to a pci soundcard (Creamware/Sonic Core Pulsar II) with ADAT interface.

No sound, just a noise (like a continuos whistle in high frequencies) comes from the Oasys. System clock of the oasys is set to Internal and the board is 48khz (like stated in the Manual).

can somebody help me please?

(maybe this problem has already been raised before but the search function of the forum doesn't work and I got a 404 error)

SanderXpander · Post by **SanderXpander** » Sun Oct 09, 2011 2:47 pm

The Oasys is set to internal, but is the Pulsar set to external in that case? Usually soundcards also default to internal.

TagPass · Post by **TagPass** » Mon Oct 10, 2011 11:50 am

Is your word clock cable hooked up? Exb-di doesn't work with word clock by default unless you've had the Adat board service by an authorized technician.

Once the search function is back working, there's a whole thread about this particular topic.

However, it works fine without using word clock, so long as your OASYS is set to internal and your card is either set to the same clock rate, or setup to sync to the external source.

SanderXpander · Post by **SanderXpander** » Mon Oct 10, 2011 8:41 pm

I don't use digital connections very often, but I thought it wasn't enough to have them simply match clock rates? I always understood one had to be master and one had to be slave?

TagPass · Post by **TagPass** » Tue Oct 11, 2011 12:00 pm

SanderXpander wrote:I don't use digital connections very often, but I thought it wasn't enough to have them simply match clock rates? I always understood one had to be master and one had to be slave?

Yes, you are correct. When using the Adat connection, OASYS is the master and the sound card is slave. When using the spdif connection, I've found no adverse affects in the audio so long as both devices are set to the same sample rate, regardless of which item is set to master or slave. Probably not the proper way to do things, but I got tired of switching my sound card from external to internal sync whenever I was optimizing audio at a sample rate other than 48kHz... But it does seem to work that way!

But back to the OP -- the whine he describes is exactly what I experienced while trying to use word clock a few years back. A sample rate mismatch, on my system at least, sounds like digital popcorn -- constant, but random clicks and pops.