Jensen Power760 4-Channel 760 Watt Amplifier (Black) Rotor Accurately Positions Outdoor Antenna For Best Reception Variable Low Pass Filters 40 - 240 Hz (12 Db Per Octave) Variable High Pass Filters 40 - 400 Hz (12 Db Per Octave) Variable Bass Boost 0 - 12 Db At 45 Hz Low Level Pass Trough Rca'S (Channel 1 & 2 Only)