Hi NZdave,
I wanted to get a mono mix of the LR mix and compress/limit it for foyer speakers in a church installation that I just finished Thursday where I installed a new EV speaker system and a QU24 with AR2412.
The 70 volt amp that feeds the ceiling speakers in restrooms, hallways and foyer needs to remain at a reasonable “consistent” volume. I wanted to use the Alt Out knob so users could very easily adjust the volume of the peripheral speakers.
I decided to use the left side of Matrix 1-2 and use the processing in the Matrix out. This does not allow the ALT OUT knob to be used for that purpose, but it does accomplish what is more important and that is a heavily processed signal for bathrooms, hallways and foyer. Unfortunately, the matrix outputs are STUCK in stereo, and there is no way to combine the left and right for a mono output. So, in short, if I use the Matrix 1 output, the foyer speakers will not get any audio that is panned hard right in the LR mains. Not a big deal.