Polk 5-Channel Digital Power Amplifier

Efficient Class D design
High-speed MOSFET switching power
Protection: Thermal, DC offset, reverse DC voltage and short circuit protection.
Sub 1/Sub2 Input
SUB/INT Source Switch
SUB Sonic Filter
Remote Bass Level Control
Rear Full, HPF Switch
Channel Mode Switch (4CH/ST)
Nickel-plated wire terminals and RCA connectors ensure maximum signal transfer
Stainless steel hardware throughout
Signal-to-noise (Referenced to rated power) > 102 dBA
Input impedance: > 20k Ohms
Overall frequency response: 20-20 KHz main channels, 20-250 Hz sub channel
Dimensions with panels: 1.81″ H x 13.31″ W x 6.75″ D