Tom Whitwell at MusicThing points to an incredible eBay find — an original Wurlitzer Sideman, the first commercially-available drum machine, just as I’m editing an electronic music history chapter that mentions it. Ironically, the most important contribution in the history of the Sideman was probably ANNOYING future Korg co-founder Tadashi Osanai. To tell the story quickly:

1. Osanai gets a Side Man.
2. Osanai plays accordion backed by his Side Man at a club owned by Tustomu Katoh.
3. Osanai is frustrated with the capabilities of said Side Man.
4. Osanai builds a better alternative.
5. Osanai and Katoh found a new company called Keio Gijutsu Kenkyujo (wow, that rolls off the tongue) to build them. The product is the first of the company that will become — Korg.

There you have it: if there had been no Side Man, there would probably have been no Korg. (See the history of Korg Corporation for more.) The Side Man is the first commercial drum-machine product if you use the term broadly, though an uneditable “foxtrot” setting isn’t exactly what most of us think of when we think “programmable rhythms,” meaning Korg itself probably deserves some credit. In the non-commercial category, the Rhythmicon I think most nearly qualifies as the first drum machine, with keyboard-controlled rhythmic patterns and a global tempo setting. The creators: composer Henry Cowell and none other than Leon Theremin. (Yes, that Theremin.) So maybe when the Soviet Union kidnapped him from his home eight years later, they just wanted him to invent disco. We’ll never know.

Here’s the fun part: Nick Didkovsky has built a Web version of the Rhythmicon you can play online. Try it yourself at the American Mavericks site.