A DP/2408 combo would be a good fit between a mobile DA-78 rig and PT in the studio. If you're running 3 DTRS machines, transfers would be simple. Plug into the three TDIF jacks on the 2408, record all 24 tracks in one pass, and you'll get 24 SDII files of the exact same length. Plug the drive into your PT system and drag each file to the same start time on it's own track. Finito. Even the slowest G4 could handle these basic duties.
If you're running 32+ tracks, you'll have to do more than one pass, which creates extra steps. You could just add another 2408 expansion unit to the same PCI-324 card to maintain the easy one pass/ equal length files functionality. Otherwise, you could add a MOTU Digital Timepiece which gives you sample-accurate sync between the DA-78s and DP. Then each pass would be aligned, but the files would have slightly different start times, so you'd have to go through bouncing each track from zero to import them into PT easily. Pain in the butt. I've never tried it, but you might be able to intiate each record pass as an automated punch-in to assure each pass has the exact same start time. Damn, why didn't that occur to me before? I'll have to give it a try tonite! (I just re-read your post and saw you only use three machines, so that was useless info, ah well... )
So the file transfers are dead simple if you record all 24 tracks in one pass. Just set-up your DP machine to use the same format HD as your PT system and you can work directly from the same drives. I use an UW SCSI card with an external case that has an UW to ATA adapter in it. Then I just swap $80 80GB ATA drives in the external case for different projects. $1/GB is pretty decent for PT media isn't it?
I haven't used Beat Detective so can't help there. DP has something called find tempo which can be used with audio files for lining things up on beat, is that similar? It also supports Vocalign for Soundreplacer like tasks. As far as soft synths, the faster the G4 the better, but DP does do a faster than real-time bounce to disk, so rendering them as audio files isn't such a time-waster if you're short on processor. I don't think you can mute by region in the current version. HTH
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