Hello, I have a query for you guys. I have a Yamaha 640 Amp which is 6.1 compatable, but I only have it set-up as 5.1. When I play LOTR in DTS 6.1, the centre rear light on the Yamaha's display lights up, even though the amp is set-up as only having 5 speakers. Does this mean that it is actually sending the rear centre signal to the rear left and right channels? Or am I missing out on some effects because I have no rear centre? What would be a good, cheap centre rear? Does it need to be as big / good as the centre front or should it be the same as one of the rear left / right's? Currently I use Eltax Milleniums for rear and front centre, with Eltax Galaxy's for front main. Thanks, Tony.