Nothing At All
Ruled out so far: , the mixer settings, the cables, the room's sound system
Check the master
- Raise MASTER to 12 o'clock. Raise BOOTH too.
- Find SEND / RETURN on the mixer and switch it off. On a DJM-900NXS2 or DJM-750MK2 there is also a RETURN TYPE switch: set it to AUX. On INSERT the mixer puts whatever comes back from an outboard unit in place of your sound, and if nothing comes back you get silence with every fader up. On a DJM-A9 the same thing lives under MULTI I/O.
- Then look behind: a processor between the master out and the amps. If something is patched in it is the venue's. Ask before you pull it.
Gear in the master path
A DJM has no insert jack. What it has is a SEND / RETURN loop that can be pointed at a channel or at the master, and venues also patch processors between the mixer's master output and the amps. Either can silence the room with every fader up: the loop because on INSERT it replaces your sound with what comes back, the outboard processor because it is powered down or sitting in bypass. The loop is on the mixer and you can switch it off yourself. Anything patched in behind is almost certainly the venue's: ask before you pull it.
Words for the tech: "Is there anything in the master path, on the send and return or between the mixer and the amps? If it is dead, can I go straight out of the master?"
Sound in the room?
You follow these steps at your own risk. Full disclaimer.