Yamaha DX21

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"First introduced in 1985, the DX-21 is the "little brother" to the famous DX-7 workhorse (which was heard on many of the big hits of the 80's and 90's) and part of the DX family that also included the DX-27 and DX-100. The DX-21 utilizes "FM Synthesis" to create its sounds and this model has four separate "operators" or parameters which can be adjusted to create the final patch.

The DX-21 has a 61 note keyboard, 128 presets, 32 RAM voices and three play modes: Single, Split (keyboard split in 2 parts) and Dual (2 voices mixed). Programming your own sounds is pretty simple once you get the feel for FM-synthesis and the unit also features MIDI (in, out, through), a cassette interface and connections for pedals (portamento, sustain, volume), breath controller and a headphone jack.

An owners manual can be downloaded here.