Technology of the GM Series\nFrom dramatic distinction to dramatic design, Pioneer's new GM-Series amplifiers are thrillers in every sense, pushing the limits of flexibility and functionality.\n\nVariable HPF\nVariable HPF (high pass filter) allow for adjustable frequency from 40 Hz to 500 Hz* and greater car audio system flexibility according to subwoofer characteristics and personal listening preference.\n\nGrowing Power, Shrinking Size\nNew Pioneer amps brilliantly integrate high-power performance superior to that of previous models in space-efficient sizes for flexibility of installation in various car cabins.\n\nAutomatic Signal Sensing and Turn-On\nPioneer amplifiers automatically select the proper input signal mode, either RCA or speaker level. When the receiver is turned on, the amplifier automatically turns on. When connected to an OEM receiver or a receiver without RCA output and utilizing speaker level output, the amp automatically senses the input mode and powers up in sync with the receiver.\n\nWhen connected to an OEM receiver or a receiver without RCA output using speaker wire, the amplifier is turned on at the same time as the receiver. Pioneer's amplifiers automatically detect the input signal and select RCA level or speaker level.\n\n- 520 Watts Max Power\n- Automatic signal sensing and Turn-ON\n- Variable high pass filter\n- Speaker level inputs