Stupid question, for components do I need a 2 or 4 channel amp?

Installing a component system in a 2010 Tacoma Access Cab (no rear speakers), I am currently looking for an amp to power the components (they are ordered - Polks SR6500's). My question is, should I power them with a 2 or 4 channel amp?

If a two channel amp is sufficient I am looking at the Alpine PDX-2.150 as I think the size will be perfect to "hide" underneath the drivers side seat. Any thoughts/experience with this amp?

Thanks in advance,

 

2 channel wil do 2 speakers, 4 channel=4 speakers.
If you go 4 channel, get one with remote controls so you can adjust the fade on the front to back speakers.

 

If you aren't running rear speakers you can get away with a 2 channel...another option is get a 4 channel and bridge a couple to run a sub and leave two for the front speakers.

 

You can always do whats called Bi-amp the speakers, which means using a 4 channel amp. You would use one set of channels for the tweeters ( I always use the fronts) and the other set of channels for the woofers. This works better if you have an amp with high and low pass crossover settings. You would use the high pass settings for the tweeters, usually anything over 4 or 5k is fine for most tweeters. The biggest thing to remember when doing this is that it is distortion, NOT power that kills speakers.