Class A amplifiers are desirable for the high quality of their sound, but, because of the configuration of its transistors, a pure class A amplifier is inefficient and runs very hot.

By far the most common car amp design, Class AB amps run cooler, and therefore, more efficiently than a class A, with low distortion and high reliability.

Class D amps (usually used to power subwoofers) boast higher efficiency, produce less heat, and draw less current than Class AB amps. Class D amps produce higher distortion, but this distortion occurs at high frequencies that are typically removed by a low-pass filter and is therefore inaudible.

Class BD amps give you the super-efficient design of a Class D amp with the clarity and sound quality of a Class B amp.

Class D amps are the best for subs
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