written by Matthew Reed

Orchestra-80 advertisement from 80 Microcomputing

Software Affair advertisement from the
July 1980 issue of 80 Microcomputing

Like many personal computers at the time, the TRS‑80 Model I had fairly primitive built-in sound capabilities. That changed in 1980 with the introduction of the Orchestra-80, a small $79.95 unit that plugged into the TRS‑80 and could play music with four simultaneous voices over a six octave range. Orchestra-80 was sold by Software Affair, Ltd., a company created by Bryan Eggers and Jon Bokelman. It became one of the best remembered hardware add-ons for the TRS‑80.


Orchestra-80 had predecessors in two earlier kit products for S-100 computers. In 1977, Software Technology Corporation introduced the STC Music System, which featured “Musical Arrangements by Jon Bokelman.” In 1979, after the STC Music System was no longer available, California Software Co. introduced the Software Music Synthesis System. Also created by Jon Bokelman, the Software Music Synthesis System, or SMS, maintained the same syntax as the STC Music System, even though it was a completely different product.

According to Bryan Eggers, Jon Bokelman demonstrated a prototype system for the TRS‑80 (presumably a variant of the SMS) at a computer club meeting. The club members were amazed when the prototype played Bach in four-part harmony. Some even looked under the table for a tape recorder to see if they were being hoaxed! The demonstration was impressive enough that Eggers and Bokelman founded Software Affair just a few days later and Orchestra-80 was born.


The Orchestra-80 manual describes the included software as consisting of five components integrated into one program:

  1. A digital synthesizer with a six-octave range that could play three notes simultaneously (four if the Model I was equipped with speedup hardware such as the Archbold Speedup Board). The synthesizer used four “tone color registers” to imitate four instruments: trumpet, oboe, clarinet, and pipe organ. Changing the registers could synthesize other instruments or “make strange new sounds.”
  2. A music language compiler which allowed transcription of written music into a form that the Orchestra-80 synthesizer could understand. The Orchestra-80 language was not just a simple representation of sheet music, but a language of its own:

    The music language was designed to allow the direct transcription of virtually any written music to a symbolic form used by the computer. Non-musicians will find the language simple to learn and easy to use since no previous musical training or knowledge is required. Yet, in spite of its simplicity, the language has all the features and capabilities required by the advanced musician.

  3. A full screen text editor for entering the musical code.
  4. A file manager to load and save music on disk or tape.
  5. Configuration routines to allow important software options be saved between sessions.

Because of the specialized nature of music itself, I suspect that the Orchestra-80 initially appealed primarily to experienced musicians. But that changed after users began transcribing music for the Orchestra-80 and making it available on bulletin board systems around the country. After this happened, even musically inexperienced users could play music on their Orchestra-80 and it became well known. One musician named Robb Murray even created a 45 RPM record called Classical Mosquito! which consisted entirely of music rendered using an Orchestra-80.


The Orchestra-80 was monophonic only, but this limitation was addressed in 1981 with the introduction of the stereo Orchestra-85. The Orchestra-80 remained less expensive than the Orchestra-85 and continued to be sold for several years. But both were soon overshadowed by a more popular model, the Orchestra-90 for the TRS‑80 Model III and 4 in 1982.

Categories: Hardware, Sound