Digital Out ~ Digital In

[spicyitaliano]

I'm interested in taking a digital output from an LE system to an HD system. Two channels is fine, eight channels (ADAT) would be even better. What do you recommend for the I/O setup on each system? Which options should be checked in the hardware setup menu to accomplish this. Thanks.

[andrewSF]

Assuming you've got a 002 or 003 (since you're talking ADAT), just connect the optical out from the 00x to the optical in on your 96 or 192. I'd sugges you clock the 00x to the HD system (rather than the other way around), so connect the word clock (the regular 1x one, not the loop/256x one) out from the HD interface to the word clock in on the 00x. Under Hardware Setup on the LE rig set the clock source to word clock. In your I/O setups create whatever paths you need on each rig, assign your tracks to the appriate ins and outs and make your transfer. Make sure your sample rates and bit-depths match, of course, but other than that it should be smooth and easy.

[Craig F]

well 002 does not have a Word Clock input so you would need to run a SPDIF or Light Pipe connection from your HD interface to your 002 and set the LE rig to clock to the incoming digital signal
003 has a Word Clock input

should work fine, you could even send MTC from your Sync I/O to the 00x to transfer in time

[spicyitaliano]

Thanks Craig and Andrew.

Well, I gave it a shot and got audio going no problem. But I want to make sure I have the digital clocking set up correctly. Let me tell you how I have things set on each system.

The LE System:
Hardware Setup -> Clock Source set to S/PDIF. Should this be set to "Optical S/PDIF"? I assume this means that it's sending the S/PDIF protocol over the Optical lightpipe connection. Can the audio and clock signal both be sent over ADAT? I guess I'm asking if it's even necessary to have an S/PDIF connection AND an optical lightpipe connection.

The HD System:
Hardware Setup -> Clock Source set to Internal (My 192 IO will act as master). Digital Format set to S/PDIF. Again, should this be set to "Optical S/PDIF" instead? Still not sure if I can have the audio and the clocking signal going over the same protocol... And of course under the "Digital" tab I have "ADAT 1-8" selected.

[spicyitaliano]

While I'm not positive if I have the digital clock set up properly, I know for sure that I cannot have the clock and audio going along the same digital connection. I tried this on my HD system's hardware setup dialog. With "Optical 1-2" selected as the 9-10 input, I then switched the Digital Format to "Optical S/PDIF" and it cleared my input selections and set them to "None". So I guess I'll need a S/PDIF connection for clock and a lightpipe connection for the Optical (for audio).

[andrewSF]

So let me see if I have this straight... You're trying to use the 8-channel ADAT Optical connection transfer information from your 002 to your HD rig with a 192 IO, right? I'm not in front of any machines so this is from memory but I think you basically want to do this:

Connect an optical cable from the 002 optical out to one of the 192 IO's optical ins (either the one near the power cable or the one on the digital I/O card). Connect another one from one of the 192's ADAT outs to the 002's in.

In the Hardware Setup for the 002 set the clock source to ADAT. I think there might be a seperate option somewhere to select ADAT or S/PDIF for the optical format. If you're trying to transfer more than 2 tracks you want ADAT. Don't set anything to S/PDIF. S/PDIF and ADAT are two different digital formats. They can both use the optical ins and outs, but you must select one or the other, you can't do both at the same time.

In the Hardware Setup for the 192 make sure the clock is set to internal. Don't select Optical (S/PDIF), this switches the optical port (I think just the one next to the power cable) to 2-channel S/PDIF mode. You want to make an 8-channel ADAT connection. Select the Digital tab and select ADAT as the format there (your other choices should be TDIF and AES/EBU). Go back to the main tab and set up your inputs for the ADAT port that's connected to the 002.

The ADAT optical signal can carry the clock as well as audio information. Same with S/PDIF. When practical it's preferable to use a word clock connection rather than clocking to the digital transfer connection, but you're just passing data (no AD conversions) so it should all work just fine.

I think you're just getting confused by the fact that the optical connectors can be set to S/PDIF or ADAT. Stick with ADAT and you should be ok...

[albee1952]

After a little head scratching, I am still wondering to what end is all this for. Why not just transfer the session into the HD machine?

[andrewSF]

After a little head scratching, I am still wondering to what end is all this for. Why not just transfer the session into the HD machine?

ZOMG! That's a really good question, isn't it? I'm embarassed to admit it didn't even occur to me to ask.

I just thought, someone wants to do this thing, here's how... So, um, why are you trying to do it this way?

[spicyitaliano]

Hey Andrew, spot on man. I think you essentially restated my exact setup, but in your own words. Good to see we're all on the same page here. Now I feel good about the way I have everything configured.

No I wasn't getting confused about using the S/PDIF protocol over ADAT optical. But I'm sure you would agree, Digi has some interesting ways of approaching digital formats, ofetn locking them down. For example, only one digital output from the LE systems at a time...why? Plenty of other digital devices handle more digital options at once. Why - it's because they're just skimping on the development. It was good to see they pulled their heads out of their asses and added word clock to the 003 line.

Now to answer the all-wondrous question: Why am I doing this? "What is this guy doing? Why not just transfer the sessions? Duh! This guy must be a moron..."

Well, I'm not quite the moron it may seem I'm working with a client right now who plays a lot of virtual instruments live in the studio. He's got them all configured on an LE system. Now most engineers would take the easy way out and just take the audio outs, going from D/A and then back to A/D into their systems. Not me - I want to take the digital out right out of the system. And the best part is that he usually uses four different controllers and VI's at the same time, so I can actually take four stereo pairs digitally through the ADAT at one time, right into the system. It's a cool setup! And now if any of you guys ever get a client with this sort of situation, you'll have this trick in your pocket.

[andrewSF]

For example, only one digital output from the LE systems at a time...why? Plenty of other digital devices handle more digital options at once.

Actually you can use the coax S/PDIF output on the 002/3 at the same time as the ADAT optical output. You can just connect it to the coax S/PDIF in on the 192 and you'll have two more digital outs from the 002. Since you're clocking via ADAT to the 192 anyway it should be properly clocked. Just add another output on the 002 and an input on the 192 (I think you need to select the rca S/PDIF in the 192's Hardware setup as well, again don't select optical S/PDIF) and viola, you've got 10 digital outs.

I'm working with a client right now who plays a lot of virtual instruments live in the studio. He's got them all configured on an LE system. Now most engineers would take the easy way out and just take the audio outs, going from D/A and then back to A/D into their systems. Not me - I want to take the digital out right out of the system. And the best part is that he usually uses four different controllers and VI's at the same time, so I can actually take four stereo pairs digitally through the ADAT at one time, right into the system. It's a cool setup!

Nice, makes perfect sense. I usually get guys running Logic on their laptops doing this kind of thing, but no reason not to do it with LE and a 002/3.