GComp2 is a compressor featuring a band-pass filter and a gate.
The compression is controlled with the Attack, Release and Compress parameters. The Compress parameter controls the compression curve, replacing the usual threshold and ratio parameters.
The level of the signal going into the compressor also affects the result. The Gain parameter controls the input gain. The Output parameter can be used to control the output level.
The gate is actually an expander, which turns the signal down when it drops below a given threshold. The Gate parameter sets that threshold.