The OPTI series of monoblock amplifiers pack a huge punch. It's equipped with several variable filters and boosting options, including a low-pass filter, high-pass filter, bass boost, and variable frequency. OPTI amps are bridgeable for increased power. Nickel plated screw terminals provide low-noise connections between the amplifier and your speakers. 1 x 3000 Watts RMS @ 4 OHMS 1 x 4000 Watts RMS @ 2 OHMS 1 x 6000 Watts RMS @ 1 OHM Mono Block Subwoofer BIG POWER Amplifier 1 Ohm Stable MOSFET Power Supply PWM (Pulse-Width-Modulated) System Glass Epoxy PCB Gold plated RCA Inputs Gold plated Line Outs Custom Terminal Block for Speaker Connections Thermal, Overload Short Protection Variable Low pass Filter (50Hz~150Hz,24dB/Octave) Variable Subsonic Filter (15Hz~40Hz,24dB/Octave) Phase Control 0-180 degree Remote Bass Control Input Impedance:10K Ohms Soft Turn On/Off THD: 0.1%. S/N Ratio: 90B Input Sensitivity: 200mv~4V Freq. Response: 20Hz~250Hz Dimensions :10.08'' (W) x 2.12'' (H) x 27.6'' (L) Sold as: Unit