The RP147 is a line level rack mount signal processor for electronically duplicate the sound of a rotating horn speaker cabinet. It has a two way crossover network as well as simulated bass and treeble rotors. It may be controlled by the front panel, remote foot switch or MIDI program changes. SPECIFICATIONS: Accurate simulation of "Leslie" fast, slow and brake Front panel and foot switch control of all functions MIDI control of all functions Chorus and vibrato modes Will phantom power all Rolls MIDI foot controllers Speed may be controlled by controller #4(controller not included) GREAT condition! clean front panel with couple small scratches, has some minor tiny dings from previous use. USED, TESTED, WORKS GREAT.