I have a 4channel amp. Would it be possible to use a 2channel LOC (freebie) to RCA inputs for the fronts and the line level inputs for the rear? Then I would chain the mono sub amp using another RCA. I was hoping I could use both line level inputs and have RCA output, but I guess amps don't do that.

 

as long as you can get one set of RCA outputs from your loc, you can always use y-splitters to create extra outputs. Check you amp though, it may have 2/4 ch switch to allow one set of imputs and internally send the signal to the rear...also many amps have pre-outs to run to another amplifier (sub).

 

What deck? What amps? Let me know and I will see what I can find for you.
Nick