This article introduces a new non-linear distortion synthesis technique, Split-Sideband Synthesis (SpSB). The technique is based on a variation of three well known distortion techniques, Waveshaping, Singlesideband modulation and Frequency Modulation. The basic technique is outlined and the relationship between these three techniques and SpSB is discussed. A reference implementation is presented, as a Csound5 user-defined opcode, followed by illustrated examples. The article closes with a discussion of enhancements to the basic technique with the use of multiple SpSB processors.