This is a programmable reverb effect, based on the hardware algorithm of the Sony PlayStation game console. All parameters are fully configurable, and it includes several reverb presets based on available documentation of SDK settings.
It supports mono which it upmixes to stereo, stereo, and 4 channel surround signals. 4 channel is spread between front and rear, so the included upmix which converts stereo to 4 channel with silence in the rear will spread the front signal to the rear as reverb. (Another channel mixer would also be suitable for upmixing other sources, or for downmixing 5.1 to 4.0.)
Version 1.1 highlights: Implemented a more hardware accurate alternate version of the DSP filter which downsamples the input signal to 22050Hz for the reverb processing, then upsamples it again to mix the output. Requires a resampler DSP to be installed to function.
Version 1.2 highlights: Fixed a typo in the hardware accurate reverb filter that broke 4.0 surround support.
1.2, released on 2010-06-30