Yes, ditch the center channel. In home audio, you do not add speakers willy nilly without sending it the proper source signal, same goes for the car. The center channel receives a center channel signal in a home theater application, not a left, not a right, not a mono... You don't want to just send the center channel some funky mono signal and have it mess up your imaging. If you want to do THX or 5.1, you'll need to have a source unit that can provide you with the signals you need. In addition, you'd probably want to put one of the best midrange tweeter combos you can find for that center channel since most of your voices will be coming from it. It's overkill unless you are competing or want a full blown theater system.
If you lost your center channel speaker today you would not miss it at all. I took mine out and never looked back. :wink: And as for the # of channels on an amp, the reason why I like 3 channels is that the sub channel is usually a mono channel with a class D amp. This makes for a more efficient amp that can put out more power for it's size, runs cooler and draw less current from your alternator. Class D amps have low feedback and minimal switching distortion. In addition, you can stick with smaller gauge wire since it is drawing less power. I would have very few choices if I wanted a small 4 channel amp that puts out 65 watts to my front channel and 340 watts to my sub. Of course there are fewer 3 channel amps out there but I think they are perfect for our cars. There are more 5 channel amps you can use and you can thus bridge the 4 channels into 2 and then have the class D sub channel. That would put out a sick amount of power.
