I am currently in the market for a new 5.1 home cinema set-up. I have decided on B&W M1 speakers. I need a bit of advice on what sub would be suited with these speakers and what would be a good Amp to power them. I have been looking at a BK XLS400 sub as i have seen and heard some preety good reviews. My budge is around £500 fro the Amp and the same again for the Sub. Any help would be much appreicated as i am a novice when it comes to these kind of set ups.