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Oberheim Four Voice Synthesizer FVS Tour Inside & Technical Overview – Synthchaser #148

https://youtu.be/sMaqV7fHyTg

I’m going to be doing some repairs on this Oberheim Four Voice synthesizer and I thought I’d make a repair video on it. But first I want to provide some better context for the repair work that’s to come. So in this video we’ll look at the inside of the Four Voice, see the different modules that make it up and discuss how they work together to make an amazing synthesizer.

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Korg MS2000R / MS2000 DSP Troubleshooting & Repair – Synthchaser #146

New synths seem designed to be disposable, or repairable by replacing a whole board, which often costs more than the synth is worth. Today we do board level troubleshooting and repair on this Korg MS2000R that had no output and gave a “MPUtoDSP check error”.

00:00 Intro & where I’ve been the last few months
02:48 The problem & troubleshooting plan and setup
06:08 Oscilloscope probing
12:27 Removing the old DSP chip
14:33 Soldering the new DSP chip
16:15 Test and head off for a cold drink

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Oberheim OB-X and OB-Xa Memory Protect Switch

Recently got a question from someone unable to save patches on his OB-Xa.  “Where is the memory protect switch located?”.  On the OB-X and OB-Xa, the memory protect switch is located on the main processor board inside the case.  To access the switch, you will need to unscrew two screws on the left and right of the synthesizer to lift the front panel and access the board.   The switch is located as indicated in the pictures below.  On the OB-8, someone finally got a clue and moved the switch to the back panel where it can be accessed without opening the synthesizer.