Thanks PENG\nI still need an external amp to power the extra pair of speakers. I'm careful with noise levels. I'm learning that the extra power for me at least is to have good clean sound and not so much volume.\n\nYou are connect it is about clean sound, but power that you don't need will not make your sound cleaner. If your master volume is at around -15 to -10, even with a 20 dB peak that THX allows for, your sound will remain "clean" during that momentary peak. People who made the point of power requirement for clean sound, often exaggerated it to get attention. Again, I am not discouraging you from getting amps, I got a few in my system too. I am just saying there is no rush, and hold out for the best deals.