Car Stereos: Amp Class, class d amplifier, rms power

Question
I was looking at an amp for sale and I noticed that it's a class D amp.  Does the class have anything to do with the sub?  Do you have certain subwoofers for a certain class of amp?  Or can any amp go with any sub as long as the impedance and rms power match?

Answer
Hi Jeff,

"Can any amp go with any sub as long as the impedance and rms power match?"

Yes.


Class D amplifiers are used almost exclusively as subwoofer amps.  They tend to be highly efficient, and can produce lots of power without generating as much waste heat, or drawing as much current from the vehicle's charging system, as a comparable class AB amplifier (the other common type).  The design of a class D amplifier makes it well suited to playing bass; it's harder to build a class D amplifier that will play the full audio range.  Because of this, nearly all class D amplifiers are mono amps made exclusively to drive subwoofers.

In the context of matching the amp to the sub, the amplifier class doesn't really matter.  Power is power.  You'll want to match the sub's power and impedance rating to the amplifier's RMS power rating, regardless of the amp design.

Hope this helps!

Brian