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Oberheim OB-X

“Vintage Oberheim OB-X 8-Voice Synthesizer from 1979 with Encore Midi Retrofit – in excellent original condition.

This Oberheim OB-X is a 61 key, polyphonic analog synthesizer, featuring dual oscillators (with sync and FM), noise generator, resonant 12dB low pass filter, dual ADSR envelopes, an LFO, 32 presets, tape interface, and CV IO.

I’m a composer for TV, film and video games and I’ve used this OB-X extensively since I bought it the ’90s…sadly I don’t use it like I use to and it’s time to pass it along to someone that will love it as much as I have over the years. I remember searching long and hard before I found this particular OB-X, I believe I’m the second owner…the first owner took exception care of it before I got it.

This OB-X is most likely a Rev1 built in 1979. Over the years I’ve seen folks replacing caps, resisters, mini trim pots, etc. on their vintage synths and whoever buys this OB-X may choose to do the same – but it still has all the original electronic parts and components and works great for me and sounds incredible! I’ve done two mods since I bought it, the Encore Midi Retrofit was installed back in the ’90s and I replaced the memory backup battery a few years ago. The only thing not working is the led on the Noise “Half” Button selector that doesn’t light up when turned on, it was like that when I bought it.

The Autotune works great, especially after the synth has warmed up for about 30 minutes. The original eight voice cards are in tune all across the keyboard and sound big and fat – but if you want them all in pitch perfect tuning you could have a true synth technician/specialist to do a calibration-tuning on the all eight cards/voices. To me, a slight variance in pitch on the collective eight voices is how I remember these synths sounding from the 80s:)

I’ve kept it in my smoke free studio ever since I bought it in the ’90s with a cover when not being used. The keyboard is really clean and great looking. The letters and screening are exceptionally bright and sharp. There are marks on the bottom, that’s the way I got it (see photos) and a few small scratches on the external metal casing. The side panels are in great condition (not real wood but they look fantastic). Some of the screws look like they might have been replaced but they all look like what I think the original screws look like. The keyboard is in excellent shape, and all keys feel in great shape and work well with no glitching.” Click here to visit listing on eBay