Allen&Heath iDR-4 - Manual (Page 33)

iDR-4 User Guide 33
Loop back system
This example shows two iDR-4
units connected with the audio bus looped back from the last
to the first. This means that all inputs are available to both units
using the patchbays and matrix. Note that each unit must have
its own session of iDR System Manager running for
configuration.
The loop back system uses the audio expander ports. In this
configuration these are no longer available for plugging in the
iDR-in and iDR-out expanders.
Force sync master Because it is not obvious to the
looped units which is the audio sync master, you need to
manually assign one of the units to be the master. If this is not
done then the operation of the units is unpredictable. Do this
from within the iDR System Manager session for the unit you
want to be the master, usually the first in the chain. Open the
File menu, Preferences, Synchronisation Options window. Tick
the Force Sync Master item.
To avoid feedback oscillation make sure you do not
route any output back to itself. Plan carefully how you will
use the input and output source patchbays and routing
matrix. Make sure all your patches are created to avoid
feedback problems.
FORCE SYNC MASTER
IN OUT
iDR-4 - A
1 2 4
3
6
5
1 2 3 4
SYNC SLAVE
IN OUT
iDR-4 - B
7 8 10
9
12
11
7 8 9 10
OUT
6
5
IN
OUT
12
11
IN