outdoor movie

For an outdoor movie night I'd like to run 5.1. Can I take an AV preamp and run out of it with RCA analog channels into an adaptor to 1/4" unbalanced and then directly into my PA amps? Outlaw Audio 950 (AV Preamp) with RCA analog outs> RCA to 1/4" unbalanced adapters> Peavey 8.5 (amp 1) Left...