The db9 serial cable sync between the master deck and slave decks synchronizes playback and provides wordclock to the slave decks. So set your USB or firewire computer interface to sync to incoming optical and voila! 24 tracks via Alesis ADAT Optical. 16bit/44.1 or 48k


http://www.youtube.com/watch?v=MqSom7--tl0

Each ADAT optical connector on the rear of each ADAT will only send 8 channels of digital audio. If you wanted to capture or run all three ADAT's at the same time you will need some sort of PCI card (RME ) that accepts at least three ADAT optical connectors. Each ADAT needs to connect to the PCI card for a total of 3 optical connectors or 24 tracks in total. This card is around $1000 though whereas the MOTU option at 24 IN/OUT is only around $1400 which seems a better option to me.
 
I still think it is time to put ADAT's to bed now. There are much more elegant solutions.
 

Well, if this guy is real then MOTU has a problem with drivers.
http://www.rme-audio.de/forum/viewtopic.php?id=17778
 
Basically saying the units don't work because of it.
 If getting an internal error on that link, just try again. May be busy? I really do not know why it does not work as good as it did before.