Class-D 500.1 mono block Quick Specs - Model 500.1 - Class D mono block Amplifier - RMS 500W @ 1 ohm   * stable into 1 ohm load. * Dual Mosfet power supplies * 24 dB low pass variable crossover 45-300hz * 24 dB subsonic filter 20-60hz * 18 dB bass boost equalization variable control * Input sensitivity variable: 4V – 250mV * Two line input RCA connectors * 3 way protection Circuit: over voltage, speaker short and thermal overload * S/N ratio :> 105dB * efficiency over 86% * THD: <0.1% * size – 9.0” x2.50” x 9.5”