First of all a link to the manual:http://s3.amazonaws.com/samsontech/related_docs/XM910_ownman_v1.pdf Have a look at page 14, 9. Go out of MixOut ( line level ) into any line level auxiliary inputs left and right on the other mixer. You didn't say what the other mixer is so this is the easiest. What you will have is a sub mix of everything plugged into the Samson controllable by the controls for the line in you are using on your second mixer. There are other options which you should be able to discover by reading your manual for the Samson and the manual for the other mixer.
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First of all a link to the manual:http://s3.amazonaws.com/samsontech/related_docs/XM910_ownman_v1.pdf Have a look at page 14, 9. Go out of MixOut ( line level ) into any line level auxiliary inputs left and right on the other mixer. You didn't say what the other mixer is so this is the easiest. What you will have is a sub mix of everything plugged into the Samson controllable by the controls for the line in you are using on your second mixer. There are other options which you should be able to discover by reading your manual for the Samson and the manual for the other mixer.