MATRIXSYNTH

OLSEN Rockmate Keio Korg 1966 Vintage Analog Drum Machine Video

YouTube Published on Apr 23, 2012 by abertronic
This one is currently listed here. Pics captured earlier here.
via abertronix on eBay (RSS)
"Rebadged Keio Donca Matic Rock Mate, Keio being the name of the company before it became korg. This was made in the mid to late 1960's and is possibly the first portable drum machine manufactured.
It is a preset drum machine which runs off either a 9v battery or 9v ac adapter. It has 6 basic rhythms A- F and an interesting "solo" button. This solo button seems to have 3 functions but actually the way it works is (as it is a momentary type of switch) when you hold it down you get repeating 32nd notes - but if you manually press momentarily you can get 16th or quarter notes.
In any case this solo function enables you to vary the limited presets by a fair amount by introducing the ability to add your own poly-rhythms. Its a wonder why this function didnt appear much on later units as it transforms a rather boring preset drum machine into something much more useful.
Please check out this and other vintage japanese gear on my ebay store."

Update via abertronix in the comments: "If I have time before it sells I'll try and draw up a diagram. Great little circuit and all values are actually written on the board. Interesting to note the designers name "T.OSANAI" credited on the board. Tadashi Osanai was one of the founders of what went on to be known as Korg."

Polyoptics: sophisticatedfinishes - Teenage Engineering Op-1

YouTube Published on Apr 23, 2012 by Axiomatick

"make'n models and paint'n beats."

Polyoptics: earbrain - Teenage Engineering Op-1, Elektron Octatrack.

YouTube Published on Apr 23, 2012 by Axiomatick

"Messing up loops from the op1 in the OT. Probably going a little bit overboard on the OT."