The Quilcom Harpverb was inspired by Pianoverb and
Sympathizer but is, of course, my own take on such an effect system.The
original idea was to simulate the sound of a harp or piano, with the
sustain (damper) pedal pressed and when excited by an input signal. This
gives a chromatically tuned type of sympathetic reverberation.
The download includes the fsm, VST, presets and a
User Guide.