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.
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)
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!
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
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.
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.
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.
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.
In this video series, I’m repairing one of each different version of vintage ARP Odyssey! In this installment we look at slider repair and replacement options, keybed refurbishing, and what capacitors need to be replaced.
In this video series, I’m repairing one of each different version of vintage ARP Odyssey! In this installment we go over the differences between models, tear them down and compare their innards!