zeusone2

so im planning on buying myself an alpine SWS 1243D TYPE S(900W power capacity and 300W max rms) sub and i already have 4 6012i infinity(180 watt peak) speakers. my question wich is the best amp for the money? anything real specific to look for? tanks

Corksil

peak power means nothing. peak power is how much power the component can handle (speakers) for one instant split second.

rms power is what you should be looking at - it means root-mean-square which translates to average power handling. This is how much continuous power it can handle without being damaged. This is the number you want to know for the speakers.

alpine makes decent audio amps. however what you want to do is find an amp that...
-has 4 output channels
-roughly matches the RMS power ratings of your speakers (on each channel)

remember peak power is irrelevant. you can also slightly exceed the RMS rating on a speaker because music is dynamic. If you were playing a test tone (one solid frequency, like a beeeeeeeeeeeeeeeeeeeeeep sound) then the power going to the speaker would be static (fixed, not changing wattage by much.) When you're playing music, the power to the speaker fluctuates considerably. When the cymbals clash, there is more power. When the drummer starts wailing on the drums as hard as he can, there is more power.

You also have to factor in volume - if you play the music at maximum volume with the gains set correctly, there will be no distortion (crackling noises) coming from the speaker. You don't want to turn the music up and hear poor quality and distortion. This is the theory behind gains, they help you tune the amp and head-unit to work together. Gain means - % gain. Like if you have the gain set at half it's 50% gain from the original signal. This means the signal coming out of the amp is 50% more powerful than the signal going into the amp. To further confuse things there are efficiency ratings on amps which make calculating exact numbers more difficult. Class B, D amps...

best of luck getting your system worked out, post up anymore questions for answering.

and don't skimp on the wiring. use 0awg to your amp, directly from the battery and don't forget the fuse. Make sure your grounds are equal size and screw them in tight enough that you could hang on the wires if you had to.

Arthas

300W RMS seems for 4 speakers sounds about right. You can get away with a 200W RMS though, since the HU wont be giving the speakers 200W RMS.

Corksil

RMS power rating for these speakers is 60wrms. 4*60 = 240wrms to power them appropriately. If it were my car, I'd feed them 80wrms ATLEAST so 320wrms. To do things right, it'd be more like 400wrms for the speakers, then a separate amp for a sub.

Your 1st post said the amp was 300wrms/4speakers = 75wrms per channel (assuming it's a 4 channel amp) ---- this is good enough for 96% of the peeps who listen to music in their cars.

In my car I have 4 speakers rated at 100wrms, all 4 are getting 200wrms and have been sounding quite good and loud since I installed them years back.