SYNC HD WITH PTHD CONNECTED TO SECOND COMPUTER

[gw sound]

Hello-
I just purchased the SYNC HD to link up a couple of computers, and am fairly new to doing this with ltc.
Here is what I am using:

Big Ben as master clock
PTHD with one 192
SYNCHD

I have a second computer running Logic with a MOTU Express that can receive ltc. I simply want to slave the Logic computer
to my PT rig so they can run locked together. I don't intend to sync my systems to external video any time soon. I believe in my case I will be generating the ltc in PT sessions, and the SYNC will be transmitting that ltc to the logic computer.

The thing that confused me is that the instructions show to connect the SYNC and 192 with loop sync, but then say that loop sync should only be used with multiple interfaces.

Also, I am not sure whether I should send the wc from big ben to one either the sync or 192, then out of that unit to the other, or to send wc from big ben to both units separately.

Any help or tips would be greatly appreciated.

Thanks in advance

[Craig F]

ok, no need to shout it your heading

take WC out from the Big Ben to the WC in on the Sync I/O and to the MOTO if it has it
Loop Sync out of the Sync I/O to Loop in on the 192
Loop out of the 192 to the loop in on the Sync I/O (you would go to other 192s in order if you had them)

LTC out of the Sync I/O to the LTC in on MOTO

in Session Setup set to Generate LTC

put the session on line [ command + j ]

[gw sound]

Sorry if the caps bothered you- I am used to a couple of other sites that use caps in the heading.

Thanks for your reply, I will try it out. Just one question- I don't need wc going in to the 192 as well?

[Craig F]

you can run WC to the 192 if you like but sense only one Digi interface is clock master at a time and the Sync I/O is what is syncing to the outside world I myself would not bother unless you are connecting to a digital console of some type and other apps will be using the 192 then yes run a WC line from the Big Ben to the WC in on the 192

[gw sound]

Thanks a lot- that clears it up for me!

[Tweakhead]

Craig is dead on with his info.

I would recommend that you consider doing away with LTC however, and using MTC and MMC to lock the two systems.
LTC is slow and does not provide simultaneous locating for both systems.
There is a very informative thread here:
http://duc.digidesign.com/showflat.p...v=#Post1170446

Also, do a search for these various terms and you will find much educated information about these topics.

[gw sound]

Thanks tweakhead- that was actually my thread last year. Since then I have had the two systems locked via mtc, and it hasn't been problem free. I get a slight drift. I am trying to achieve a lock between the two systems that is tight enough that I can have some tracks on both playing together without any drift whatsoever. I have had various problems with using mtc:
sometimes the slaved computer with Logic plays back pitched down
sometimes the slaved logic computer plays about a sixteenth of a second behind
sometimes the systems lose their lock all together and the Logic computer plays back intermittently

I just bought the SYNC for this purpose alone. If I am going in a direction that won't make these problems go away, could someone please explain to me the path I could take to get the two systems rock solidly locked?

Also, I still don't understand if I am to use the loop sync going both ways to hook up the SYNC to my PT rig. The manual plainly states that loop sync is to be used only if you have more than one interface. I only have one 192. Is there an other way I should be hooking them up?
A different and better way to lock them together?

[Top Jimmy]

I would take word out of the Sync HD to the Big Ben. The Big Ben will regenerate the clock and then it should feed clock both to the 192 and the MOTU interface. Ignore the loop sync completely.

The reason you might like to do it this way is that the Sync HD will switch the Big Ben's rate for you whenever you open sessions with differing sample rates. The only thing you have to do in the session setup is set the 192 word in as master and then switch it back to the Sync HD. The 192 will stay on the word clock input. Logic also needs to be on the word clock in of the MOTU. This way, both systems are synced to the same sample clock and won't drift.

http://www.apogeedigital.com/pdf/con...ro%20Tools.pdf