QSC ISA 500TI - 70V Power Amplifier. Any wear can be seen in the photos. Please ask any questions you may have before placing a bid. QSC ISA amplifiers are an ideal, cost-effective solution for fixed installation applications requiring low impedance or distributed loudspeakers. There are seven models in the line, four low impedance models (ISA 280, ISA 450, ISA 750, ISA 1350) rated down to 2-ohm loads and three Ti versions (ISA 300Ti, ISA 500Ti, ISA 800Ti) featuring isolated transformers for 25, 70 and 100 volt distributed audio systems. The DataPort V2 Lite connection facilitates the use of amplifier accessories (XC-3, LF-3 and SF-3.) providing economical crossover and subwoofer filtering solutions. Features: Low-impedance outputs plus isolated 25, 70, and 100 volt outputs for distributed audio systems Rear panel gain controls for tamper resistance; 2-dB detents allow for quick and repeatable settings. XLR and detachable Euro-style input connectors DataPort V2 for use with DPV2-compatible signal processing accessories (XC-3, SF-3, LF-3) and DSP-3/DSP-4 (with external power supply) Independent defeatable clip limiters for reduced distortion Selectable high-pass filters (30 Hz or 70 Hz) protect speakers and prevent speaker transformer saturation with minimal effect on program material Front panel LED indicators include power, signal, and clip Covered barrier strip output connectors for safety agency compliance Automatic on-demand variable-speed fan: quiet normal operation, with maximum cooling when needed Rear-to-front air flow helps keep equipment racks cool Stereo, bridge, or parallel operating modes Comprehensive protection circuitry including DC, infrasonic, thermal overload, and short circuit protection.