The PV amplifier features a two-way crossover and sub-sonic (low-cut) filter for each channel. Crossover frequencies are fixed at 150 Hz, allowing subwoofers to be driven at extremely high sound pressure levels, and the filters cut at 40 Hz to prevent low-end rumble. Using proven technology gained through years of amplifier design, this unit takes advantage of rugged TO-3P output devices mounted on massive aluminum extrusions and dissipates heat via an extremely quiet and effective two-speed fan. PV amplifiers are designed to operate at line voltages as low as 50% of nominal, employing mammoth toroidal power transformers and offering impressive specifications and features not found on similarly priced competitive units. This amp is designed to drive a 2-Ohm load per channel, thus achieving awesome performance levels into 4 Ohms in BRIDGE mode. PV amplifiers are ruggedly constructed, rack-mountable pieces of gear with superb patching capability, allowing superior flexibility in application. Front panel features include calibrated, detented gain (dB) controls and LED indicators for power (PWR), signal presence (SIG), Thermal Protection indicator, and DDT™ activation on each channel, as well as a rocker mains POWER switch. The back panel contains an IEC connector, line voltage selector switch, dual primary fuses, and the critical cooling fan opening. This opening should have an adequate supply of cool air and should never be blocked or restricted. Also on the back panel are the input and output sections, including an input barrier strip for permanent installations. Each channel input section includes a combo XLR / TRS phone jack connector, THRU/LOW out and HIGH out TRS jacks, and activation switches for the LOW CUT filter and crossover (150 Hz XOVER). Channel output sections feature dual shock-proof binding posts and four-conductor twist lock connectors. An additional four-conductor twist lock connector allows BRIDGE mode output.