chase lock problem

[najrebe]

I am having problems with my #2 slave xt locking with the brc. I am investgating the one setting on the brc called ext sync mode. Could someone explain the two options here- "frame lock" & "lock & release". The manual didn't describe these two features at all.

Or if someone has a some general advice for this problem. It is hard to predict when the XT's would lock up. Sometime immediately and sometimes after 20 seconds the #2 slave would still be chasing.

Thanks

 

[Sound Cracker]

You gotta get to the "source" of the problem here...

First off, I can not help you one bit without knowing first WHAT you are asking to ADAT's to sync to. Another digital deck? A computer? Reel to Reel? Cassette 4 track?

Frame lock means that the BRC will follow SMPTE time code on a frame by frame basis. You need very stable incoming SMPTE for this to work.

Lock and Release means that the ADAT's will initially lock to incoming time code then run "free" from it after that. Not a good option if you really need to keep everything running exactly together like for music recordings. This was used more for syncing to video then anything else, where the sync didn't need to be quite so exact.

ADAT's are extremely fickle about syncing to External time codes. You have to assure that the incoming time code is very stable in timing (the why of this if very complicated, but it has to be). A couple of culprits to corrupting the incoming time code could be time code that is "stripped" on tape that is next to a very hot track, like a snare drum. Also, bad cabling or too long of a cable run can make the data bad. If your SMPTE is on analog tape, it needs to be recorded and played back without any noise reduction at all.

If you are trying to sync your ADAT's to any analog tape machine other then say a Studer or Otari, good luck! Few tape analog machines have transports that run stable enough to feed a stripped SMPTE code to the BRC for the ADAT's to lock to.

Hope this has been a little helpful.

Good Day!

 

[najrebe]

Thanks Sound Cracker

Thank you very much. That was very informative.

When you say "external time codes" does that include or exclue the BRC?
I was only testing this problem with the BRC and my 2 xt adats. I did have an external word clock being the master of the BRC clock but I then turned it off and set the BRC clock to internal.

With only the BRC and adats running I initiated a playback and the #1 adat locked immediately then #2 is the "fickle" one. I have no SMPTE stripped. I thought in this setup the BRC would produced SMPTE through the 9-pin sync connection and that is what the adats would lock to.

I am also going to switch some wires around to try and detect a faulty wire.

I am also not implementing any analog tape in this setup. So I think I can eliminate that possibility.

Thanks

 

[Sound Cracker]

I see....

Okay, in this case I would try making the "fickle" ADAT the master deck rather then the slave deck.

This could indicate a problem though with that particular ADAT. Keep a close eye on it to see if other problems exist. Watch the LCD display for error messages. They could mean that you have a part to replace or dirty heads possibly.

I am sure though that switching the decks will probably solve the problem, at least for a while. ADAT's can run very smooth and reliably, or have all sorts of syncing problems with multiple decks in a system. It is a crap shoot that Alesis has never really solved, although they claimed to with the lx and xt 20's. You COULD jump up to the M20 deck, but each of those will set you back around $4000! Yikes!!!

Hope the advice solves your problem.

Good Day!