I suspect we're all staring at the Apogee Duet specs figuring there's probably some clever way to make the second set of audio outputs (headphone jack I guess) output a mix of the two channels and hoping someone else actually knows the answer.

In the meantime, my guess is what you need is a headphone plug, a couple of resistors to mix the signals (one end of each resistor goes to a pin on the headphone plug, other ends are soldered together to give you a combined signal), and an RCA phono cable with one end cut off so you can solder one end to the connected end of the resistors and the other end to the headphone plug's ground.

I'm sure there's a factory in China that makes just that assembly for 275,000 other companies to resell but I wasn't able to find one...

EDIT -- the high level inputs might work too and would definitely be the easier answer... probably would need the sub's level control turned up higher since the high level inputs are expecting signals from a power amp but AFAIK the usual settings are pretty low anyways.

Last edited by bridgman; 11/24/14 07:35 PM.

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