Triadex Muse Simulator Home Page


Development of the Muse Simulator is nearly complete. All features described in the specification are included in the current (May 3, 1997) build. A few questions remain about whether the behavior of the current code matches the original Triadex hardware.

What is the Muse?

The Muse Simulator is a MIDI sequence generator. It takes a few parameters from its front panel controls and generates a series of MIDI note on and note off messages. It also sends program change messages. MIDI Device and Channel number can be selected. For a more accurate simulation of the original, the Simulator can also produce square waves.


The Muse Simulator is based on an early electronic musical instrument, the Triadex Muse. It has been claimed that the Triadex Muse was the first digital device for making music. The original Muse was designed by Edward Fredkin, now at Carnegie-Mellon; and Marvin Minsky. now at the M.I.T. Media Lab; in the late 1960's.

Pictures of the Triadex Muse may be found at various on-line sources, including Hal Layer's Mind Machine Museum and the Virtual Synthesizer Museum.

The Muse is the subject of U. S. Patent 3610801, which gives much detail, but clarifies nothing.

An article by Don Lancaster in the February 1971 issue of Popular Electronics magazine described the "Psych-Tone", based on the same concepts, but not as complex as the original Muse. This article includes a side bar with a picture of the Triadex Muse and the text:

"A recently introduced unit which is quite similar to the Psych-Tone is the Muse. ... With 14 trillion note combinations, the Muse has four switches for volume, tempo, pitch, and fine pitch and eight slide switches. Four of the latter vary the interval and thus determine the notes, while the other four control the theme and varaiations of the melody."
SWTPC (South-West Technical Products Corporation) produced a kit of parts for the Psych-Tone.

The internal logic of the Muse was described in detail in Hal Chamberlin's book, Musical Applications of Microprocessors.

An earlier program, based on some of the same descriptions as my latest version, but capable of five-note polyphonic output, has been found at this FTP site in the Netherlands. It is also available from the author, at (EXE and related files).

This program is called "ANKLUNG" and was written by Paul Kriwaczek in 1994, using Visual Basic, version 2. The older program will presumably run under 16-bit Windows. Thanks to Greg Williams, one of the Friends of the Muse, for this information.


A functional specification for the latest version of the Muse Simulator is available here. This program is designed to use the same internal logic as the original Triadex product.

Download Instructions

This page has a link to the Muse Simulator. If you click on the picture below, your browser will download the file via ftp. The Muse Simulator is a Windows 95 application. It was built with MFC 4.2 and uses Windows 95 Common Controls in the MFC and AFX libraries. It will probably run under Windows NT as well. It requires the file MFC42.DLL. If you don't have MFC42.DLL, Microsoft may be able to give you a copy.

Muse Simulator, version 1.1

Muse GUI

This program is Freeware. It is supplied "as is" with no warranties regarding its operation or possible side effects. Use at your own risk. This version is an early beta release. The documentation is on the next page.

The Muse is not in the public domain. It may not be sold or redistributed without permission from the owner. Please feel free to link to this page, or send me email with questions or comments.


Thanks to my Beta testers: Terry Leigh Britton and Bruce Adams, who have provided many helpful comments and corrections, and an icon.

Special thanks to Tim Thompson for sending me excerpts from Hal Chamberlin's book, giving the original logic of the Triadex device. I am grateful for Tim's advice, and his archive of computer music literature.

Thanks to Hal Layer for advice and for sharing an anecdote regarding the inventors.

Thanks to Alex Takessian for sending a copy of the original owner's manual for the Muse. This helped clear up some important details of the implementation.

Thanks to Bill Wetzel for a copy of the original white paper from Triadex, and copies of a number of press clippings.

And thanks to the other Muse owners and fans who have sent messages. Your feedback makes this fun.

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This page was last updated on 29 March 2001.

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