A monophonic synthesizer is a synth capable of playing only one note at a time. Some of the best-known and most versatile synths ever designed, including the Minimoog, Odyssey, and most modular synthesizers, were/are monophonic. See also polyphonic. Some synths which are inherently polyphonic have a mode, often referred to as a "solo" mode, in which the synth restricts itself to playing only one note at a time. Some styles of soloing benefit from this. If the synth has the ability to split the keyboard, the solo mode might apply to only one part of the split. See also unison.