The Epicenter® Bass Restoration and AccuBASS® both enhance bass, but from differing approaches.
The Epicenter is designed to add bass that is not already there; AccuBASS is designed to enhance bass that is there, but is perhaps weak or rolled-off slightly in a factory sound system.
The unique bass restoration circuit of The Epicenter, originally patented by AudioControl, looks at the upper harmonics and uses them to digitally recreate low frequency fundamentals (original frequency) that have been lost through compression (MP3s), rolled-off, or simply removed (during mastering). The Epicenter digital restoration occurs from 27 Hz to 63 Hz and may be parametrically shaped using the Wide and Sweep knobs on The Epicenter Concert Series and The Epicenter InDash.
AudioControl’s patent pending AccuBASS circuit is designed to recover the bass that goes missing when the volume is increased in some factory sound systems. Unlike The Epicenter®, AccuBASS is more like an EQ, which boosts from around 50 Hz to 125 Hz; AccuBASS will not add content which is not already present in the signal. AccuBASS can be set to activate only when the bass in the factory system begins rolling off (using the Threshold knob). The end result is a smooth bass response at all system volumes. Alternatively, AccuBASS may be switched to “always on” (again using the Threshold knob – turned fully clockwise) to give rich enhancement to the low end of your music, for systems that do not exhibit a bass roll-off.