We troubleshoot and repair a vintage Oberheim OB-8 synthesizer that has no audio output. I show how to replace the key contacts on the keyboard.
Author: synthchaser
Dead Roland Juno 106 Repair – Synthchaser #178
We troubleshoot and repair a Roland Juno 106 that isn’t powering on or booting up.
Oberheim Matrix 6R and Matrix 1000 Repair – Synthchaser #177
I pulled a pile of broken rackmount Oberheims out of my storage and got down to repairing them to make them ready for new homes. I’ll show you around the inside of these synthesizers and we’ll troubleshoot and repair a variety of problems… Doesn’t boot at all, boots but no sound, makes sound but has dead voices, and voice is alive but incorrect pitch.
00:00 Intro
00:42 White Matrix 1000 & inside tour
04:30 Black Matrix 1000
18:59 Matrix 6R & inside tour
Moog Sonic Six Functional Demo – Synthchaser #176
The Moog Sonic Six is a rare, portable analog synthesizer with classic Moog tone and ladder filter, featuring dual VCOs, ring modulation, and a built-in speaker—all housed in a rugged suitcase-style design perfect for studio or stage. Its unique sound-shaping capabilities including X/Y modulation, configurable keyboard modes, and vintage character make it a prized collector’s piece and a powerful tool for experimental or classic analog synthesis.
In this video we take a functional tour and explore exactly how the Sonic Six works and what it can do.
01:32 Direct Output Mixer
02:50 Oscillator A
05:15 X/Y Waveform Generators (LFOs)
09:31 Oscillator B
11:40 Keyboard Modes
15:07 Ring Modulator
16:30 Contour Generator & Articulator (Envelope Gen & VCA)
20:50 Voltage Controlled Filter
Vintage Oberheim Two Voice Synthesizer TVS-1 Repair – Synthchaser #175
In this edge-of-your-seat exciting installment of the Synthchaser synthesizer repair video series, your host Synthchaser undertakes the repair of a vintage Oberheim Two Voice Synthesizer that is suffering from a dead SEM (Synthesizer Expander Module, or “voice”).
Parts, service and synthesizers available on my website. I buy broken synthesizers!
My multimeter: https://amzn.to/3Ltgqi3
My desoldering tool: https://amzn.to/3PikaEf
Soldering station: https://amzn.to/3rudVF4
ARP Avatar Guitar Synthesizer Repair – Part 2 – Synthchaser #174
We continue the repair of the ARP Avatar, first repairing a problem with the synthesizer section, and then try out the guitar interface with the special hex pickup. Of course it’s not working, and we track the problem down to the D’ module which converts a guitar string to a control voltage. ARP never published the schematic for this module, but we use some basic troubleshooting skills to figure out the problem and get the Avatar working as a guitar synthesizer.
00:00 Intro & recap
00:48 Troubleshoot & repair of missing VCO 2 Square Wave and Filter LFO modulation
07:21 Controlling the Avatar with a vintage ARP Odyssey
08:15 Testing the guitar interface with the hex pickup
12:56 Troubleshooting and repair of string to CV conversion
20:56 Success!
23:56 Thoughts about the ARP Avatar and conclusion
My oscilloscope: https://amzn.to/3rm6b8d
My multimeter: https://amzn.to/3Ltgqi3
My desoldering tool: https://amzn.to/3PikaEf
Soldering station: https://amzn.to/402LjBh
Parts, service and synthesizers available on my website. I buy broken synthesizers!
ARP Avatar Guitar Synthesizer Repair – Part 1 – Synthchaser #173
In this video we have a look inside the ARP Avatar and see how it differs from the ARP Odyssey. We tear the synthesizer down and begin repairing it, fixing a short circuit in the trigger extractor circuit board.
00:00 Intro
01:20 Tour inside
04:29 Synthesizer teardown
07:55 Board E has a short circuit!
10:39 Replacing capacitors
14:41 Filter enhancement, switches and sliders
My desoldering tool: https://amzn.to/3PikaEf
Soldering station: https://amzn.to/402LjBh
My multimeter: https://amzn.to/3Ltgqi3
Summer Closure
Synthchaser will be closed from June 17 to June 30, 2025. Orders and inquiries made during this time will be processed the week of July 1. Thank you for your support.
ARP Soloist 2700 Functional Demonstration – Synthchaser #172
Take a rare ride into synth history with the original ARP Soloist Model 2700—the predecessor to the legendary Pro Soloist. This vintage gem delivers a quirky, expressive palette of preset sounds and touch-sensitive effects that set it apart from the crowd. In this functional demonstration I run you through the different presets and touch sensor effects found on this synthesizer.
Quadruple ARP Odyssey Synthesizer Repair – Part 3 – Troubleshooting & Final Demos – Synthchaser #171
In this video series, I’m repairing one of each different version of vintage ARP Odyssey! In this installment I bench test and repair faults with the 4075 filters, keyboard tracking, and a dead oscillator. Then we look at and listen to the finished Odysseys.
00:00 4075 Filter testing & repair
01:18 Keyboard control voltage repair
02:49 Dead oscillator repair + earthquake
08:42 Mk I White 2800 Finished
09:20 Mk I Black & Gold 2800 Finished
10:18 Mk II 2813 Finished
11:41 Mk III 2823 Finished
