The CPX Series is available in four models, the CPX 1, CPX 2 class A-B, and CPX 3, CPX 4 Class-H, with power ranging from 480W to 1,600W per channel. The amplifiers are designed to operate at line voltages as low as 50% of nominal and can drive loudspeaker loads down to 2 ohms per channel or 4 ohms when set to bridge mode. An Crest Audio feature of the CPX Series is the GCL™ (gain comparator limiting) system with a rear panel defeat switch. The GCL monitors input/output gain, reduces the signal when distortion or excessive high current conditions occur, and protects the loudspeakers from dangerous transients and unexpected level changes.
The CPX Series offers processing capabilities, including two channel independent crossovers and a subsonic filter. The crossover frequencies are fixed at 150 Hz (CPX 1/2/3) or 100 Hz (CPX 4). The crossovers have direct outputs with THRU/LOW out and HIGH out TRS jacks. Channel output sections feature dual binding posts (CPX 1/2/3) and four-conductor twist-lock connectors [Which I guess means unbranded SpeakONs?]. For inputs, the CPX Series features combination XLR/¼-inch connectors with an added barrier strip for permanent installations (CPX 1/2/3).
The CPX Series front panel offers calibrated gain (dB) controls and LED indicators for power (PWR), signal presence (SIG), thermal protection, and distortion detection activation on each channel. A front panel rocker switch controls the mains power. The rear panel contains an IEC power connector, line voltage selector switch, dual primary fuses, and a two-speed DC cooling fan opening. Rounding out the back-panel features, the CPX Series offers the mode selector switch for stereo and bridge-mono operation, a toroidal power transformer, and a line voltage selector switch for 115V or 220V to 240V AC operation.