Mix recording with no booth/record out

I'm trying to record the mixes a play at my college parties. I have a denon S120 so my only outputs are the master outs (1/4" and RCA) is it possible to have the 1/4" out to the amp, and the RCA out to my audio6? I typically keep the master vol jacked up pretty high, because my amp (receiver actually) likes to overheat and shut off for a few minutes, and I keep it jacked up pretty high as well (these are college parties).

In ripping some vinyl a few weeks ago for my dad, I found that I had to keep the channel gain somewhere are 1-2 o'clock, and the master no high than 10 o'clock, otherwise there wasn't just a little clipping, but a lot. and these were jazz records. smooth paul desmond to boot.

Is there any way around this? software that can limit the levels maybe? I use a DVS (TSD2) with an external mixer (duh) so that takes internal recording out of the picture