Alesis Studio 12R Reference Manual page 25

4, 6 & 8. On the ADAT-XT, press and hold [ANALOG INPUT]
and the REC READY keys for track 1 or 2 to activate this "built-in
patch bay" feature.
2. Plug track outputs 1-8 of the ADAT to LINE IN 1-8 of the
"monitor/mixdown" 12R.
the ADAT, but on the right of the mixer, so the wires must cross
o v e r .
3. To record more than two tracks at a time, plug a mono cable
from the INSERT jack of any channels of the mixer to the input
of any track. By plugging the cable all the way in the INSERT
jack, and not returning the signal from the recorder, the
individual channels will be removed from the stereo mix. This
way, you can record a stereo mix of several inputs on any two
tracks while simultaneously recording individual sources on
other tracks.
Studio 12R Reference manual
Note that output 1 is on the left of
Connections
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