KAC-8104D or KAC-7204 car amps?

Question

The first is D class and the second AB class. They're about the same price and will push two 12" sub woofers. Store says the AB amp is a step up. Is it really?

Answer 1

For a subwoofer amp, a class AB is not necessarily a step up from a Class D amp.  It's certainly not something on which to base a buying decision.

The real difference between the two amps is that the KAC-7204 is a 2-channel amp, and the KAC-8104D is a mono amp.   If your two subs are single voice coil, 4-ohm type, the KAC-8104D is a much better choice (provided the subs are each rated for at least 250 watts RMS).  If the subs are dual voice coil, 4-ohm subs, then the KAC-7204 may work better.

The two amps are not comparable in terms of power ratings.  If the store is trying to tell you that the only real difference between the two is the "Class D" vs "Class AB" stuff, then I wouldn't pay much attention to anything else that particular employee tells you.  Pick the amp that will more closely match the power ratings and impedance of your subwoofers, and don't worry about the amp class.

Answer 2

i would get the mono D because you'll get all of your power. with a/b amps  the power is divided and you dont get all of your power.