Nobody does class D like Directed, and Viper subwoofer mono amplifiers make that clear. The compact d300.1 delivers more bass power than conventional amps twice its size and is loaded with all of the features you would expect from a high end mono amp. The Viper d300.1 features a continuously variable 12 dB/octave 2-way crossover and a variable 0-12 dB bass EQ function that gives that added bass emphasis that your system needs. The variable input sensitivity accepts up to 8 volt input, making it compatible with any source unit. Other goodies include a rugged one-piece extruded heat sink, injection-molded mounting feet, and gold-plated wire terminals and RCA connectors. Features full thermal, DC offset, reverse polarity and short circuit protection.