While it is physically possible to connect an output of your mixer to the 1/4" mic input of the SL1 for recording, we highly discourage doing so for the following reasons:
1. Connecting a line level output to a mic input can overload the mic pre-amp and damage the mic circuit as the Mic input adds about 30dB of gain to the input signal.
2. The mic input is mono only. If you use a "Y" cable to connect a stereo output into a mono input, each output (left and right) tries to drive the very low impedance of the other, forcing both outputs into current-limit and possible mixer output damage. As a minimum, severe signal loss and distortion results. For more information about using "Y" cables see here: www.rane.com
If you wish to record using your SL 1 please use recording software (such asAudacity or Garage Band) and use the inputs of your laptop's soundcard , or preferably another soundcard with another computer.