DESC: The exterior features a black anodized brushed aluminum chassis with a silk-screened MB Quart logo and illuminated red Quart rectangle, adding a classy touch to any install. Detachable end panels hide all wires for a clean, uncluttered install. A focused mass aluminum heatsink maximizes efficiency and whisks away the heat from this Class A/B performance power house, while MOSFET output devices guarantee excellent sound quality. The PAB series also features an excellent crossover network with excellent flexibility. The crossover network features hi and lo-pass crossovers, and if need be, can also be used in bandpass mode for dialing in the exact frequency response of your drivers. A 24 dB subsonic filter is perfect for eliminating low end frequencies when using a ported enclosure with your subwoofer. Need a little extra boom? Dial up the Vario bass equalizer for up to 18dB of bone-throbbing bass.