SOLIDAC: computer music from a small Scottish computer

SOLIDAC was a small transistor computer (1024 words memory, 32 bit) designed by Paul Thomas (late of Brock University, Ontario) and built by Tom O’Beirne of Barr & Stroud, the Glasgow precision instrument maker. The machine was commissioned in 1963, after Thomas had left Scotland for Canada. It was in use at Glasgow University until the 1980s.

Although running at a rather pedestrian 30 kHz, O’Beirne did find some interesting applications. This included producing music from it, a couple of examples being:

There’s not that much out there about SOLIDAC. There’s an ACM research article “Solidac: An Early Minicomputer for Teaching Purposes” (1993) and an archived reference from Bill Findlay: The SOLIDAC Computer.

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Very nice! I notice a mention from the gplus days, so see also:
In 1963, the first computer built in Scotland was completed” March 2015

There’s a video linked in the comments, and from the description there we find a page which says

The track that follows that of Tsuchiya is Enneadic Selections by Thomas Hay O’Beirne, another man as interesting as unknown to most people. O’Beirne is a Scottish mathematician who during the sixties began to be interested in non-scientific computer applications, like the music. In 1965, on the occasion of a public meeting, O’Beirne was able to come up with an intervention focused on music, numbers and computer. In the following years he conducted further experiments in computer music with a computer Solidac, by developing a software called Orpheus, which probably was also used for this Enneadic Selections (1968). It is a song featured with dated timbrical solutions, but O’Beirne tried a curious synthetic reproduction of sounds of bagpipes, as you can hear from 3:32, perhaps a tribute to his native land.

(As noted, it’s not certain that we’re hearing Solidac itself here.)

Another post from gplus, this time from Hans PUFAL:
I am researching a unique computer, the SOLIDAC” April 2015

In both cases, worth a look for the comments and the familiar names here - familiar at least to those of us who were on gplus at the time!

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Sadly, most of Bill Findlay’s web content - including the links and documents about SOLIDAC - is gone. Internet Archive doesn’t have any of it beyond the top-level pages

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Is that the KDF9 Bill Findlay you’re referring to (www.findlayw.plus.com)? I may have some of his pages copied on my backup machine (though chances are only the kdf-9 related parts, unless wget -r went crazy and grabbed everything by accident) I’ll go check.
Wait a minute… http://www.findlayw.plus.com/ is still up.

I found the missing files on Greg Michaelson’s web site, at Index of /SOLIDAC/ and managed to recreate Bill’s web page in conjunction with the archived top-level page. Restored page is at The SOLIDAC Computer

(Greg is Professor Michaelson’s son and is a member of the Edinburgh Computer History Project)

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Ah, there’s an interesting link… I worked with Greg many years back and one of the things he did for fun was implement a music (well, simple tone routine) inside a real-time control system for a blood analysis machine…

When programmers get bored… :slight_smile:

-Gordon