I just bought for my father 6 alpine speakers averaging at about 250W each with and RMS of 50.

What kind of amp do I need how many watts?? The speakers are not going to be killed.

Also whats the difference between 2 and 4 ohms?

Thanks.

 

your speakers are probably 4 ohm. really a 50x4 amp will do just fine.
And usually speaker damage comesfrom under power not over power. so if you go a bit bigger it wont be a bad thing at all

and the difference between 2 and 4 ohm is that 2 ohm is less resistance