word clock sync

[unc417]

I have a yamaha digital console with 4 presonus adat pre's.

The past few months I've been getting random pops in the audio from the presonus channels. I believe it's coming from a problem with the word clock sync.

I replaced the older digimax LT with a digimax D8, and somehow it pops even worse. Instead of the occasional single pop, it pops every few seconds. It's unusable.

The LT's daisy chain through BNC. The D8 has no BNC input so it can't daisy chain, other than 1 unit at the end of the chain. I thought that adat carried word clock as well but I can't get it to sync with adat connection only.

The D8 pops the same regardless of if it's connected directly to the console or at the end of the chain going through the LT's. What are the possibilities here? Replace the BNC cable? I don't know that the word clock engine in the mixer can go bad? I'm at a loss of how to correct this problem.
Any help is appreciated.

[bobbycito]

it sound like you are having clock issues between devices when i looked at the manual for the D8 it states it has a clock in but no out an reccomends to "T" the bnc at the unit (http://www.presonus.com/media/manual...cManual1_0.pdf) pg 16 in the manual.

Also i would make sure the console is set to internal clock and the units are set to ext. sync

you can not use the ADAT sync because the signal is coming from the pre's so you have (4) different sync times arriving at your console and your comsole is set to syc to 1 of them or to its internal clock.

[unc417]

Yes the console and pres are set to the correct internal/external clock.

I would have had T's ready by the time the D8's arrived but did not know they did not have a BNC output until I received them today.

[bobbycito]

do you have a video or word clock D/A test it?

if you setup 1 D8 and loop out the old LT will you get a proper sync with the 2 pre amps?

[unc417]

no

I'm not sure what you're meaning. I can use loop through 2 of the LT's and in to 1 D8, that would work since the D8 is at the end of the chain. The D8 and the mixer reports that there is a successful sync, however the D8 pops terribly. No more than 10 seconds between pops on at least half the channels at once.

I replaced the rg59 cable and went directly from the mixer to the D8 again, but it made no difference.
thanks

[bobbycito]

you could have a bad SYNC in on the D* you could try setting the D8 to Internal Clock and set the console to Sync off the slot and channel that the D* is connected to (slot 2 line 1/2)

setup would be
D8 (set to internal sync) ADAT to Console (set to clock off incomming ADAT on slot and channels D8 show up on) then leave the LT set to external with the BNC going to the console and looping to the next unit

does the D8 dow a Lock to sync when set to external?

[unc417]

The D8 and console shows a successful sync. I may be wrong and the pops be coming from something else, but the word clock is my only guess at this point.

If the console has the option to use an external clock, I haven't found it.

[bobbycito]

which console are you using?

[unc417]

DM1000

If the word clock configuration can change, I haven't. I don't know what else could have changed.

I will also try some new adat cables.

[bobbycito]

in the display access if you push DIO you will see the word clock page

[unc417]

Yes. But it's merely an informational page. I see nothing there that lets me accept a clock sync from another device.

Even if I did that, that would sync 1 D8 and the mixer but what about the other D8's? I need 3 pre units.

[bobbycito]

you arror over to the selected box and click eneter and it should ask you to confrim change of clock source