Q: As stated in the manual, Mic channel 1 is linked to the Telco channel's Talk switch as default.
I understand that changing this factory setup requires opening the case and locating the appropriate link connection.
That will be no problem. However, before proceeding with the change, I have a question:
Is it possible to link more than one Mic line to the talkback channel?
A:
The mic feeds are taken post channel EQ and summed to create the talkback mix.
Any or all of the mic channels can be added to this mix by adding or cutting the link wires on the rear PCB of the mixer.
This is shown on the block diagram in the User Guide (p14).
The jumpers can be found on the Logic PCB, which is labelled AG7456_1 (or _2), above the section labelled COMMS MIX, JP5, JP6, JP7 & JP8.
By default, there is only a connection across JP5 which is the factory preset for Mic1
Although this appears to be a straightforward process to modify, the User Guide refers you to a service centre to do the work.
With this in mind, if your unit has a valid warranty, please check with your dealer/local A&H distributor before carrying out the work as they might consider your modifications to invalidate your warranty.