Zenith 3500 is a 2-channel 1750W @ 4 Ohm professional audio amplifier, with switching power supply, built in a 2-rack-unit metal enclosure. It has balanced inputs in XLR3 format and outputs with XLN4 connectors. It has selectors for input sensitivity and operating mode. It also has protection systems against short circuit, temperature, DC, VHF and constant high frequency signal. The front panel has a power switch, independent volume controls for each channel, and power, signal, clip and protection indicators.