Power Acoustik PWM-16 Pre-Amp Equalizer 18 DB Octave Pre-Amp Isolated Pwm Power Supply Maximum Output: 8V Subwoofer Crossover Variable: 30 Hz 250 Hz Signal-To-Noise Ratio: 110 DB 1V A Weighted THD 20 Hz 20 Khz 0.05% 3-Level Parametric Eq Subwoofer Gain, Front Rear Fader, Master Pre-Amp Output Gain And Rotary Input Output Controls 1-Year Warranty