Oberheim OB-8 SN C30307

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"This a a fully restored and serviced OB8. The service was completed by Ben Watcher of Odd Frequency (Nashville, Tn). MIDI mod has been added and works beautifully. The work is guaranteed through November 2022.

This is an early version of the unit that didn’t have the “Page Two” functions screen printed on the panel, so the tech labeled them for ease-of-use and testing. They’re easily removed, but I found them useful for remembering what lived where.

It is in very good condition and sounds absolutely gorgeous. I played it for hours when I picked it up from the tech.

It is a legend for a reason. Even without effects it has a full and rich sound. Send it through some reverb and delay and you will not be able to stop smiling.

Details of service below:

Action Performed / Recommended:
- Cleaned unit and performed initial calibration
- Noted failed "Keyboard Lower" LED
- Noted failed Filter Envelope on Voice 3
- Resolved Filter Envelope by replacing U311 (CEM3310) with AS3310 (modern replicant based on original)

- Completed recommend full replacement of capacitors
- Modifications to improve power supply and voice boards
- Rebushing and rebuild of keybed
- Battery replacement OR elimination kit
- MIDI kit and install

- Complete rebuild and re-bushing of keybed
- Full replacement of capacitors and voice board upgrade
- Battery elimination kit install
- MIDI kit and installation
- Complete calibration and troubleshoot

Notes during restoration:

- Dated the keyboard production date between January 17-23, 1983
- Many of the factory modifications had been performed already and I completed those that had not
- The later models of OB-8 had a different VCA. This unit has the CEM3360s.
- There were several CMOS ICs that had failed causing erratic behavior.
- Had to build a new cable and replace the ribbon cable between the Processor and Voice boards
- Later OB-8s had a different screen print, which showed Page 2 functions. I used a label maker to indicate these features
- Fully confirmed Page 2 functions"