A new nonlinear distortion synthesis technique, split-sideband synthesis (SpSB). is discussed. The method is closely related to the well-known principles of waveshaping, single-sideband modulation, and frequency modulation. In the technique described, however. it is possible to separate the different sideband grounds (upper, lower. even, and odd) as independent Outputs. This allows for a greater flexibility Of Sound design for the synthesist, including the production of novel spectral transitions. The method and its implementation are Outlined, drawing on the relationship between it and its correlates. The use of Multiple SpSB processors is then explored, followed by a discussion of the application of the technique to adaptive effects.