I have a valve amp which I use to listen to music and am thinking of connecting this to my AV amplifiers pre-out so I can still listen to music from my valves, which i find sound much better than any solid state i've hard. Anyway that aside, it is my understanding that when watching films the input selector on the valve amp would have to be set to whatever the preout was set to. Here's my problem though, for the purpose of movies in surround sound, would the valves be controlling the sound on the front L+R or will it just be acting as a preamp and would the av amplifier still process the sound on all 5 speakers? Hope i'm making sense?