i got a simple question. I replaced the front speakers with 3 way 220 watt 6.5 pioneers and the rears with 3 way 220 watt 6x9 pioneers. they sound good as is but i was curious bout adding and amplifier to the 4 speakers and in the future when i dont have my trunk packed with my semi stuff add some subwoofers. ive done the high powered speakers and systems in my high school days and im not into it nearly as much. how many watts should i power the speakers? I don't see a reason to power them the full 220 watts so i was curious of maybe 150 each? maybe a single 600 watt amp or something. how many watts does the stock cd/cassette radio put out?