Last update: October 2005. Updated page: Summer 2001





In the seventies Clarence BARLOW applied his ground breaking theory of TONALITY in his album Cogluotobüsicletmesi: the title is the name of a Turkish busstation.

At the KlangArt Festival 1991 in Osnabrück (D), I met Clarence Barlow again. (Look back at the P-ART Journal Item #19).

He demonstrated his revolutionary improvisation program AUTOBUSK for computer controlled piano play (= Yahama DISKLAVIER).

With "Autobusk" the computer brain generates his improvisation in realtime on the keyboard. In this way of composing, the composer doesn't compose the notes anymore but prescribes the rules (rhythm, pitch, melodicity, density of notes, harmony, degree of tonality etc) to generate music that was never composed before.
Other composers like Wolfgang Martin STROH (D), Karlheinz ESSL (Lexikon-Sonate in MAX - for Mac) and Godfried-Willem RAES (B), developped algorithmic programs on PC to make the computer compose new pieces.

Autobusk is not unique, but it has deeper features than similar software.
First of all, it contains a "harmonicity" section.
Harmonicity is a concept of intervallic pleasantness, one might say, in which the purity of intervals may be determined for any set of octave divisions. For a tempered chromatic scale, the harmonicity of all notes is consistent because the divisions are even. However, in an infinitely retunable instrument, it would be possible to examine the tonal direction of a piece of music and adjust the intervals for a greater level of purity to the ear. Barlow's harmonicity theory can be applied to a complex 17-tone scale (which he used for his automatic piano piece Otoblu), or to something as simple as a pentatonic scale. Autobusk will calculate the detailed pitch relationships of greatest harmonicity for any scale pattern.
Other features of Autobusk are a note-sequence generator in several simultaneous voices with independent parameters for each one. This can be completely original (i.e., from a random-number source), or in the form of variations on a melodic/harmonic Midi input.
Autobusk originally needs an ATARI computer with only a 40-megabyte hard drive. Developped during a periode of 14 years, Clarence Barlow finished in September 2000 to release disk & manual of his AUTOBUSK.
The most interesting parameters include rhythmicity (how a rhythmic stream will vary with respect to an original); "tonicality" (how close to a tonality it will remain); eventfulness (how often a note will occur). There are also range; distance from a central pitch; the interval limit the melody may leap; tempo; note duration and embouchure; chromaticism; voice assignments and usual Midi parameters; and a number of specialized controls. (cf.: chapter Parameters of music, by Dennis Báthory-Kitsz)

Autobusk is a real-time pitch and rhythm generator. Click on the diagram and you can see the main Autobusk desktop in full display:

Bibliographical note: Clarence BARLOW, Autobusk - An Algorithmic Real-Time Pitch & Rhythm Improvisation Programme. In: ICMC Proceedings, Glasgow 1990, p. 166-168.

SPECIAL SERVICE: you can download the AUTOBUSK-program by Clarence BARLOW for FREE on the award winning alternative MIDI- homepage for Atari-users conducted by Tim CONRARDY:

Legal FREE DOWNLOAD and instructions to emulate Atari on the PC-platform VIA the following link:

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