what's the different between 2 and 4 channel car amplifier?

Answer 1

2 channels

Answer 2

THe 2 channel amp has 2 amplifiers in it the 4 channel amp has 4. You can run a 2 channel amp on 4 speakers as long as you don't go below the Ohm rating but you will have no fader control, on the other hand if you car stereo only has 1 set of RCA outputs then you dont have fader control anyway.

Answer 3

Better depends on what you are looking to do. Drive one 12" go with a 2 chnl and bridge it(making it mono). Make sure the amp is bridgeable and that the impedance of the speaker is right for that amp. You can also find a 4ch amp that has the ability to bridge 2 chnls and run 2 in stereo, known as 3channel, if you want to run two spkrs in stereo and the sub mono.
If you are getting another sub later, you can then run one on each channel of a two chnl amp, or wire them in parallel off a bridged amp.
Look at the back of your speaker, it should tell you if its a 2, 4, or 8 ohm. That tells you the amount of resistance its going to put on the amp. Most bridged 2 chinls will handle 4 ohms mono(one channel), 2 ohms mono if its a high end amp. This means you can run two 8 ohm speakers in parallel or one 4ohm when bridged. If the speaker you have now is 4 ohm you will have to get another 4 ohm and just run the amp in stereo (2 chnl) unless you get an amp rated 2ohm stable in mono.
There are many ways to wire up a stereo, or to make what you have work, its kind of hard to describe them all here.

Answer 4

"with a 2 ch amp, you can connect to it only 2 speakers" this is a false statement!!

Say my 2 ch amp is 2 ohm stable per channel (most are). I can wire two 4 ohms subs in parallel (connect all positives(+) and then connect all negatives (-) of the subs = 2 ohms) per channel. Thus giving me four subs total on a 2 ch amp.

Each sub must be no less than half of RMS power per channel.

Check here for some more tips:

http://spkrbox1.spaces.msn.com

Answer 5

2 channels

Answer 6

To make it simple; with a 2 ch amp, you can connect to it only 2 speakers ( rear speakers ), with a 4 ch amp, you can connect 4 speakers ( rear and front speakers ).
But usually, a 2 ch amp is good enough if you have a small car and don't want a very loud sound system, so you use it only for the rear big speakers, and connect the front ones directly to the car radio.
I hope I was helpful

Answer 7

2 channels will power 2 speakers (left & right)
4 channels will power 4 speakers (left & right of both front & rear)

Answer 8

One has 2 amps inside, the other has 4 amps inside.