Question about S/PDIF input with Protools

This might be more of a ProTools question actually. Here is the scenario:

MPC 1000 has S/PDIF in and out
Digidesign Rack OO3 (with Protools LE) has S/PDIF in and out

I want to interconnect the two so that I can-
1. play out of my MPC and capture in ProTools
2. play out of Protools and capture in my MPC

I have accomplished #1. I can create a track in PT, choose the S/PDIF input as its source and happily capture from MPC to PT.

I cannot however figure out #2. I either cannot get PT to output via the 003's S/PDIF out or I cannot get MPC to read from it's onboard S/PDIF in.

Any ideas? Is there anything I need to do from the MPC side to read from that S/PDIF input other than just setting the input to "Digital" when in record mode (JJOS 1 btw)

It's not all that big of an urgency as I have many other ways to output from PT and go into the analog ins of the MPC. I just like the idea of the simplified yet very high quality S/PDIF connects.

I find that sometimes you have to switch to analog and then back to digital before the MPC will pick up a digital signal. That's been the case with all the versions of JJ I've used. I never used the stock Akai OS, so I can't speak on that. I believe it to be a clocking issue. The MPC has to run off external clock when its recording from the SPDIF in. Which means that your 003 has to be clock master.

Also, be careful, there's potential for creating feedback loops with both SPDIF connections going.

make sure that your DAW is outputting 16 bit 44100 hz otherwise you will be chasing your tail for weeks.

I'm not sure but I believe the MPC will just ignore the extra 8 bits. I've never not once changed bit depth on any piece gear connected to my MPC. And I believe the same is true in reverse, a 24 bit device will accept the MPC's 16 bit SPDIF output and just fill the rest in with zeros.

mp3 wrote:I find that sometimes you have to switch to analog and then back to digital before the MPC will pick up a digital signal. That's been the case with all the versions of JJ I've used. I never used the stock Akai OS, so I can't speak on that. I believe it to be a clocking issue. The MPC has to run off external clock when its recording from the SPDIF in. Which means that your 003 has to be clock master.

Also, be careful, there's potential for creating feedback loops with both SPDIF connections going.

Yeah, I think the problem is more on the Protools side for sure. I probably have the settings wrong in there. Annoyingly I am coming up empty on the PT or 003 manual.

I didn't think about the possibility of creating a feedback loop though. Kudos on the warning. I'll watch out for that...

I might just keep with the analog inputs. The 003 has a pair of aux outs that I am not using so I can pretty easily accomplish what I want that way. Still bugs me though...hmmm

This might work.
1 Disconnect your spdif cables from MPC to 003
2 Turn everything off(PT's,003,MPC in that order)
3 Connect spdif cables and turn MPC on
4 Power 003 on
5 Boot pt's
6 New session and open your I/O settings
7 Hit default or return to original settings
8 It should now be reading spdif or digital in and out(forget how it reads exactly in ptle
9 Let me know if it works
10 Hopefully you have resolved the issue by now and don't have to do this

Digi 002's and 003's spdif I/O can be glitchy sometimes so you may have to try this a couple of times. As far as cables and ground loops are concerned,if your running long digital cables,110 ohm quality cables help quite a bit. If you have a problem with this,send a screenshot and I'm sure someone will help.

Great. Thanks for the help! I will give this a shot when I get home. I have just been using the S/PDIF out of MPC into PT and then using analog out of the aux out of the 003 and back into the MPC. Works good but I would love to keep it S/PDIF for both.