Pioneer GM-4300F 4-Channel 400-Watt Maximum Power Amplifier 4-channel car amplifier 40 watts RMS x 4 at 4 ohms (50 watts RMS x 4 at 2 ohms) 100 watts RMS x 2 in bridged mode (4-ohm stable in bridged mode) 4-channel selectable high- and low-pass filters (80 Hz, 12 dB per octave) speaker-level inputs