The very rare Steiner-Parker Minicon was released in 1977 as a simplified version of the Synthacon. Instead of three VCOs, the Minicon has just a single analog oscillator, but thanks to Steiner-Parker's engineering they claimed it actually sounded more like two oscillators, and was incredibly stable too, which was a very important feature at the time compared with some of its more popular competition.

Flanked by classic solid wood end-panels, the four-octave keyboard is graced by a clean, simple and logically laid out control panel with 17 knobs (and 19 switches) for total hands-on control. The keyboard itself could be switched between three different octave ranges (low, middle and high) and had portamento and a pitch bend knob.

The oscillator offered two waveforms (saw or square) plus a pulse-width mode as well as an independent noise source, continuously variable from white to pink noise. The resonant filter section offered three modes: low pass, band pass or high pass. A unique envelope section had Attack and Decay controls, plus ACD (attack converted to delay), which allows delayed envelopes for double attack effects. The VCA can be triggered or enveloped. A simple LFO offers square or triangle waveforms with adjustable speed and depth and is assignable to the filter and the oscillator. Additional features include Sample & Hold, Legato triggers, a CV/Gate interface for use with other gear and an internal headphone driver.

Steiner-Parker was a Salt Lake City, Utah based company formed primarily by Nyle Steiner and Dick Parker. As something of a boutique manufacturer, never achieving the mass-market production scale of Moog, Arp or Sequential Circuits, the synths made by Steiner-Parker between 1975 to 1979 (when the company dissolved) are exceptionally rare and very high in quality.