To connect the output of the Audio Advantage to your mixer: 
First read your mixer's manual.

1) Purchase a shielded audio interconnect cable with a 1/8" stereo
   (3-conductor) mini-phone plug on one end, and one 1/4" stereo (3-conductor)
   phone plug on the other end. 

2) Plug the 1/8" stereo phone plug end into the Amigo's output jack. 

3) Plug the 1/4" stereo phone plug end into one of the stereo channels on your
   mixer e.g. channel 11/12 on a Mackie 1202VLZ). Adjust that channel strip's
   Balance control to the 12 o'clock position (in the middle). 

4) Set the Audio Advantage's output to about 50%. 

5) Set the input level on the Channel 11/12 strip to about 70%. 

6) Play a selection on the computer. Adjust the levels so that the LED level
   meter on Channel 11/12 glows mostly green, with maybe just a little yellow
  (if any), but definitely no red LEDs lighting up. 

That's all there is to it.
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