Rotary Speaker Simulator

A Rotary Speaker Simulator is a device that either attempts to or fully recreates the sound of a Leslie speaker.

While many analog devices has been touted as Rotary Speaker Simulators, including but not limited to Univibe, Rotovibe, and Rotosphere, it was often only capable of simulating vibrato and at most chorus, despite the fact that a rotary speaker can also accomplish flanging, phase shifting, and even tremolo. This is because, instead of actually mimicking the way the sound wave was manipulated by the baffles and bounced around the cabinet, all the analog device actually manipulate the signal themselves. Thus, the result is one that, though pleasant and interesting, is by no means similar to the sound produced by a Leslie.

Thus, all true rotary speaker simulator have to be digital, , utilizing modelling algorithms to model the relations between the rotating horns and bass baffle, and how the sound bounce around the cabinet. As Leslie also have an amplifier section, most of these typically have overdrives to simulate that aspect. Some of these pedals can even accept keyboard's input.

In 2006, Boss released the RT-20, which is the first Rotary Speaker Simulator for Boss. Line 6, as well as DLS, also utlize modelling technology on their rotary speaker simulator.