TX81Z

The Yamaha TX81Z is a rack-mounted FM tone generator module released in 1987, played from an external MIDI controller rather than a keyboard of its own. It uses four-operator FM synthesis, and unlike earlier Yamaha FM instruments each operator can be set to one of several waveforms rather than a sine wave only; it offers eight-voice polyphony and eight-part multitimbral operation. It is best known for digital bass tones — its "Lately Bass" preset became a common sound in house and other dance music — alongside the metallic and bell-like timbres characteristic of FM synthesis.