I'm Isaac Goodwin, currently an undergraduate at Oxford University, and creator of Goodwin's Twin Eliptic Harmonograph. Since building a very rough version of the instrument seveal years ago, I've gone on to create a refined, portable model, which packs away into a box no larger than a guitar case.
I have performed with my Harmonograph at Port Eliot Festival for the last couple of years, and displayed the machine at the Larmer Tree Festival last summer. Hopefully I'll be touring with the instrument this coming summer, so look out for me at the more eclectic festivals.
The Harmonograph, invented in the 1860s, is a mathematical instrument which draws visualisations of musical chords using the combined motions of several pendulums. It reveals the nature of harmony and mathematics, and shows quite plainly that number, the one indisputable truth in the universe, creates musical and visual beauty. There are several different designs and an infinite number of forms that can be created.
The drawings below were created on Isaac Goodwin's twin elliptic Harmonograph, and show the visualisation of Near Unison, the sound produced by a single note on the accordion, where two reeds are used, tuned slightly apart, to produce a more pleasing sound. Likewise, to achieve these drawings, the motions of two pendulums, each of slightly different frequencies, are combined.
Through my work on the Harmonograph I've written a short book, available on Kindle or as a hard copy (£4 + £0.62 P+P via PayPal). The book gives a brief history of this wonderful machine, a simple look into the mathematics and music theory behind it, and a run through of the various different types of patterns that one can produce on it.