Hi,
is there an easy way to have an exact copy of the main mix on the Mix 9-10 out?
should be post fader. We´re mixing ourselves on Stage - like what u hear is what You get 
Answered a number of times - why not use alt-out…
But you still aren’t hearing what is heard out front, because of all the other factors in play (like direct acoustics from instruments/back line/vocalists…
I know that - but there is no EQ on ALT OUT as far as i Know
Thought you wanted a mirror of FOH?
Allocate all channels and returns to 9-10 as post fade, and set the levels to unity.
Any inserts or dynamics on the FOH mix will be missed.
The Alt Out has the eq and dynamics of the output sent to it, the on,y additional control it has is the level pot on the face of the mixer.
thx
If you want all dynamics included in the Main Mix you could use the old way over an analog splitter:
Main Out - analog splitter - back into a stereo channel… Best is to unassign the stereo channel from Main not to suddenly have a copied signal on the main speaker!