Housed in a rugged 3-U chassis, all seven models feature rear panel gain controls for tamper resistant operation with 2 dB detents for quick and repeatable settings. Inputs include both XLR and detachable Euro-style connectors. Outputs feature covered barrier strip connectors for safety agency compliance, and for added versatility, a DataPort V2 (Version 2) terminated with an HD-15 connector is provided for use with DPV2-compatible signal processing accessories such as the XC-3 Crossover, SF-3 Subwoofer Filter, LF-3 Low Frequency Filter and the DSP-3 with external power supply.Selectable high-pass filters are included to protect speakers and prevent speaker transformer saturation with minimal effect on program material. The ISA Series provide additional protection circuitry including DC, infrasonic, thermal overload, RF and short circuit protection.