Design

The Steiner-Parker Synthacon was a monophonic analog synthesizer

Analog synthesizer

An analog or analogue synthesizer is a synthesizer that uses analog circuits and analog computer techniques to generate sound electronically. The earliest analog synthesizers in the 1920s and 1930s such as the Trautonium were built with a variety of vacuum-tube and electro-mechanical technologies...

 built from 1975-1979 by Salt Lake City-based synthesizer manufacturer Steiner Parker. It featured three voltage-controlled oscillators (one of which could output sine

Sine wave

The sine wave or sinusoid is a mathematical function that describes a smooth repetitive oscillation. It occurs often in pure mathematics, as well as physics, signal processing, electrical engineering and many other fields...

 and sawtooth waves and two of which could output sawtooth, pulse

Square wave

A square wave is a kind of non-sinusoidal waveform, most typically encountered in electronics and signal processing. An ideal square wave alternates regularly and instantaneously between two levels...

, and triangle

Triangle wave

A triangle wave is a non-sinusoidal waveform named for its triangular shape.Like a square wave, the triangle wave contains only odd harmonics...

 waves), a two-pole resonant state variable filter

State variable filter

A state variable filter is a type of active filter. It consists of one or more integrators, connected in some feedback configuration. Any LTI system can be described as a state-space model, with n state variables for an nth-order system. A state variable filter realizes the state-space model directly...

, two ADSR envelope generators, a pink- and- white noise generator, and a 49-key keyboard. While the Synthacon was not a modular

Modular synthesizer

The modular synthesizer is a type of synthesizer consisting of separate specialized modules connected by wires to create a so-called patch. Every output generates a signal – an electric voltage of variable strength...

 system, signal routing could be achieved through a series of switches.

Users and Popularity

According to designer Nyle Steiner, "...several hundred Synthacons were made and sold." Marketed for live performance and studio use, the Synthacon was used by Earth Wind and Fire, The Doors

The Doors

The Doors were an American rock band formed in 1965 in Los Angeles, California, with vocalist Jim Morrison, keyboardist Ray Manzarek, drummer John Densmore, and guitarist Robby Krieger...

, Pink Floyd

Pink Floyd

Pink Floyd were an English rock band that achieved worldwide success with their progressive and psychedelic rock music. Their work is marked by the use of philosophical lyrics, sonic experimentation, innovative album art, and elaborate live shows. Pink Floyd are one of the most commercially...

, and Frank Zappa

Frank Zappa

Frank Vincent Zappa was an American composer, singer-songwriter, electric guitarist, record producer and film director. In a career spanning more than 30 years, Zappa wrote rock, jazz, orchestral and musique concrète works. He also directed feature-length films and music videos, and designed...

, among others .

The Synthacon Today

The Synthacon's filter remains popular in contemporary modular synthesizers due to its inexpensive, simple-to-build design. The filter is of the diode ladder family and features separate inputs for low-pass, high-pass, and bandpass modes. Many versions of this circuit are available.