Maybe this is a dumb newbie question, but can one run 6.1 on a 7.1 receiver? I'm thinking specifically about the Yamaha 657, if that makes a difference. I'm thinking about getting the Yammy and also thinking I may want a set of matched speakers (I currently have Cambridge Model 6 fronts and Yammy NS-AC3 and NS-A770 center and surrounds, respectively) and many speaker sets now are 6.1. I know I need a sub. I guess another possibility would be to pick up a pair of Yammy NS speakers, and a sub, though I don't know if current NS speakers would be matched with my 8 year-old ones. Thanks for your input. Also, any recommendations for sub $500 HT speaker sets would be welcome. I don't think SWMBO will let me go above $900-1000 on HT equip @ one time