Yes of course guys, 4-channel will be great for the sound.
However, running short of money
a 4-channel amp is really expensive even for a unsed.
what about i power the 2 front speakers(220w peak, 45 rms) with the headunit (which offers 22w rms, 52w peak), then power the pair of 6x9 rear speakers with an amp?

will the sound of front speakers worse quite bit than the rears'? if it was, i have to go for a 4-channel anyway

however, on the box of the headunit, it show the connection that using the headunit to power the front and use the amp to power the rears. is it a regular or routine connection method?

Thanks!

 

I would recommend amplifying the speakers, most head units just dont have the power to keep your speakers out of distortion and moderate/high levels. if you look hard enough there are plenty of good deals on 4 chan amps

 

What a lot of people do is run only front speakers.

Depending on what you have for front speakers, I would power the front's with the amp and power the rears off the deck for rear fill.

 

If you are getting a 2 channel amp, use it to run the fronts and leave the rears on deck power.....why, you ask??....because you want the cleanest sound closest to your ears....

Having said that, there should be a few different 4 channels in the classifieds you can get for around $100 or so that will take care of all of them....

 

Here's a link to the classified's. There is lot's for sale and at great prices in most cases.

Car Audio For Sale - Canadian Car Audio - Canada’s #1 Car Audio Forum

 

Oh my!!

When 3 different people reply within 5 minutes with basically the same answer, watcha gonna do??......

 

Hahaha. No confusion here.

 

I would buy a 4 channel and power all 4 speakers.

 

Thanks guys for the great answers.
But's it's really hard to find a good 4-ch amp around 100 bucks.
I have been following the classfield here for a while. no attractives
will go on searching
Thanks!

 

My cadence isn't top of the line SQ but it was only 150bucks. 75x4.
look into the smaller ones, trust me this is do-able on a budget.