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Interesting note about the the earlier 'block font' logo.

"The Oberheim OB-X was intended to be a more convenient version of the Oberheim Four Voice, with voice cards that are very similar to the SEM module. Unlike the Four Voice, the OB-X had a unified interface for changing parameters and proper patch storage (thirty two patches in four banks of eight). Unlike the later OB-Xa and OB-8, the voice circuits in the OB-X are all discrete components, giving it a sound much more like the SEM based synthesisers (it also makes it easier to repair as there are no hard to obtain chips).

This is one of the first ones made, with a serial number from 1979 and the earlier 'block font' logo rather than the later 'cursive' one. The serial number label also shows it was built as, and still is, a four voice model. I bought this synth in 2010 from Tonetweakers in the USA, who fully restored it before shipping it to the UK. I then took it to Kenton Electronics, who fitted a MIDI retrofit that allows the synth to both transmit and receive MIDI. As part of the restoration, the keyboard bushings were replaced so the keys are level (I've included a shot looking straight on at the keyboard to show this).
The synth has spent the last five years in my little home studio and has never been gigged, and it can be heard on a number of tracks on my Soundcloud page. This is the same kind of synth used by the likes of Japan and Killing Joke - it provides the amazing sounds on Killing Joke's 'Night Time' album, including the legendary track 'Love Like Blood'. I really don't want to part with this synth, but I need to pay for work on my money pit of a car!.."