What Ivan said... the summed mono output is for convenience and not critical about calibration levels. Often has it's own gain trim on the back.
Thanks everybody. The mixer is an Allen and Heath Xone 464, a better DJ mixer.
John, if the summed mono is just for convenience and isn't calibrated, I don't want to use it. I have 4 Labhorns that I want to fully power and limit properly, and I'm trying to learn the science behind proper levels, xover, limiter, and amp settings. I was going to use the summed mono as a feed to the C input on a DCX2496, because I could control the level to the subs with a separate main fader ... the mixer has two main busses, either of which can be summed to a mono out.
I've started with trying to understand signal sources and mixer levels..
Ivan, I'm not sure what you mean by 'how much gain it has at that stage'...Its maximum output level is spec'd @+26dbu.
Tim, the same signal is going to both channels via a y cable. I've been using a 1kz +4dbu 1.23v sine wave.
The mixer's input level meter reads 0db; and with the main output fader and meter at 0db, each channels output voltage is right about 1.23v ...so all makes sense so far and seems to be pretty dang accurate.
But then I read the summed mono (which doesn't have a trim) and get only about .9v. .... this is what throws me....
It's not a big deal if the summed mono is just for convenience and wont give a true level.... I can get around that easy enough.
It's more about finally learning and understanding how this stuff works, and not blowing up my labhorns
Thanks for the generousity of your help, Mark