Passort Designs Soundchaser and Mountain Computer MusicSystem

Passport Designs - Angle View

The Passport Designs Soundchaser Computer Music System is a package that includes a Mountain Computer music synthesizer and the Soundchaser piano-style keyboard for music input. The system hardware and software allows four-track recording and sound manipulation, using the Apple II as a controller. The keyboard case is 29" long and is made of solid wood. The keys are full-sized. A ribbon cable connects the keyboard to its interface board, which goes in slot 7.

Dave Pratt - the designer of the ComputerEyes digitizer boards - purchased this particular system new in the early 1980s and used it for his home computer music hobby. It cost over $1,200 new.

Passport Designs - Cards

The music synthesizer is a set of two circuit boards (using slots 4 and 5). It's a sixteen oscillator (voice) digital synthesizer, with software to control it. A light pen is included that interacts with the software to manipulate music on the computer screen. A stereo output is provided.

Passport Designs - Documentation

Passport Designs - Keyboard

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commodorejohn's picture

What I want to know is whether it was named for the classic Yes song "Sound Chaser." WE MAY NEVER KNOW.

Does anyone still have one of these systems? I am trying to find the keyboard controller that plugs into the Apple //.

A high-res photo will be helpful, as I suspect I will have to clone the card.

robbo007's picture

I have one. Do you still need a photo?

How does this compare to the Alpha Centauri system?


The Mountain Computer Music System cards are identical. The IO cards were similar but not interchangable.The Syntauri had a 5-octave velocity-sensitive (kind of) keyboard.  The Soundchaser was 4 octaves and not velocity sensitive.The big difference was the software. Syntauri came out first. Their software was mostly a 4-track live recording app.  Soundchaser developed something similar, but also later added a non-real-time step editor (which I wrote), a 16-track recorder, and a few other apps.While Passport Designs aimed at musicians, Syntauri tried to get into the education space.  They failed and were soon out of business.  Passport transitioned to MIDI, developing the first MIDI recording and editing apps in the US, for Apple II and Commodore 64, and later for Macintosh, MS-DOS and early Windows.

Hi. If anyone needs the keyboards I have two that I got from the local rescue mission for $30, with a manual. They both have the interface card. One is in great shape. The other is in fair shape.


Let me know.

I'm looking for a Keyboard for the Soundchaser. Do you still have one? Put together a system around 1978. Trying to do it again.