"Here is a great package for any analog synth lover. It starts with a 1980 Oberheim OB-SX 4 voice that was overhauled by Synthchaser about a year ago... Works like a dream, all voices pass autotune. Has the synth king eprom in it. 56 presets. Comes with Magic Box Midi Editor that connects to the "Computer" Interface on the back. Also comes with a Behringer Controller that has the OBSX template loaded already.. Plug it all up and you now have so many controls to edit the OBSX!!! Synthchaser calibrated th OBSX as well as installed new key bushings. All in all a modern re-do and stable synth to deliver some jaw dropping Obie pads, brass, strings, leads, basses and more! RARE to find a turn key package like this and priced low as well!"
1st Sonic Six: "The Moog Sonic Six is a rare, portable analog synthesizer with classic Moog tone and ladder filter, featuring dual VCOs, sample-and-hold, 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, and vintage character make it a prized collector’s piece and a powerful tool for experimental or classic analog synthesis. While this synthesizer is often offered by sellers at a "high on crack" price, I am pleased to offer this one for less than half of what some delusional synth dealers are trying to get for it.
The synthesizer is in good condition, but the original "Moog" logo sticker on the outside was peeled off. The power switch does not illuminate when the synthesizer is powered on. The synthesizer uses a standard IEC power cord, and one will be included. Please see photos.
This Moog Sonic Six has been serviced by Synthchaser in August 2025. Work done included:
Cleaned switches, pots and sliders
Refurbished keybed - new bushings, cleaned bus bars & contacts
Tuned & Calibrated Synthesizer"
2nd Sonic Six:
"This vintage Moog Sonic Six Suitcase Analog Synthesizer powers on and makes sound, but is being offered as-is at a discount due to cosmetic and functional issues. The A, X, and Y oscillators and the Moog Ladder filter appear to be working. This can be a great opportunity for someone willing to put a little work in to get this rare synthesizer below market. The synth is being sold as-is for parts or repair, with no returns.
Please see this video showing the functional status of the synthesizer. : [video above]
Issues I noticed (you may find other issues, but the synthesizer is still being sold as-is with no returns):
Cosmetic: A power cord has been hardwired to this unit in place of the power inlet. The exterior of the case is in rough looking condition and some screws are missing and things feel loose. The synthesizer is missing all knobs and switch caps. Some of the keys are stained. 2 rubber feet are missing, so the case needs something behind it to stay open when in use.
Functional: Oscillator B appears to be dead. The ring modulator appears to not be working (perhaps due to oscillator B not working, ring mod was not tested with external input). Key contacts are dirty and not working well, bushings need to be replaced. The contour generator appears to be broken. The Contour/Pitch Control pot for the filter was replaced with a pot that doesn't extend fully through the panel, so you can't use it. Pots, sliders and switches need cleaning. Calibration needed."
"The Oberheim DMX is a legendary vintage drum machine known for its punchy, organic 8-bit sampled drum sounds that defined countless hit tracks of the 80s, from New Order to Run-D.M.C. With its iconic swing, individual outputs, and rock-solid build, it delivers the classic analog-meets-digital groove that modern gear can’t replicate.
This DMX is in great condition and includes factory the factory MIDI and Memory Expansion board.Please see the video below to hear the sounds that are installed as some of the stock sounds have been changed. (On Reverb, this video will appear at the end of the photos list)
This DMX was serviced in July 2025 by Synthchaser. Sliders and pushbutton switches were cleaned, and the Synthchaser Battery Eliminator was installed, so songs and sequences are saved without the need for a battery that poses leakage risks and requires periodic changing by a synth tech. (I left the original factory battery sticker on, but there is no battery)."
"Really nice vintage Orange & Black late model ARP 2600 with the 3620 Duophonic keyboard. This particular synthesizer is in great shape and was on display at NAMM 2020. The keyboard controller was serviced by Synthchaser in 2020 and the main unit was tested and calibrated by Synthchaser in February 2025.
There are some scratchy sliders on the main unit, and the tolex inside the main unit's lid is coming up on one edge (can easily be re-glued). Includes an original style oval power cord."
"Arp Omni String Synthesizer. Fully working. I recapped all of the boards except the power supply because the power supply is outputing the correct voltages. All sliders have been replaced with lighted sliders and work smoothly. Synthchaser master oscillator module installed to insure good tuning. Power cord is missing the ground pin. This was a diy project, when got this it did not work at all. After the recap and replacement of sliders it now fully works and sounds good. The next owner can play it as is but may want to consider replacing the power cord, recapping the power supply and replacing the keybushings. Cosmetically this unit is nice. There are a few scratches from normal use and storage and some keys that have marks on them but nothing major."
"Rare vintage Arp Quadra synthesizer keyboard that just got back from a full servicing by Synthchaser. Work included a complete re-cap, new slider pots (which can be led activated at a later stage if desired), new touch panel membrane and keybed refurb. It's fully functional and good to go. We have a long demo video made by Synthchaser we can share on request. The only issue worth mentioning is the lower transpose button is not working, but the upper transpose button does work and performs the same action. We have sold Arp Quadra's in the past for $12k - $15k and it's been a couple years since we last listed one for sale. These are very cool vintage analog synths."
"This synth has been fully serviced and upgraded, making it IMO the best and most musically usable Quadra you'll likely ever come across. Modifications installed are the Synthchaser Quadra MIDI kit (very few of these kits in existence, I believe there were only around 20 of them made/sold, and it is no longer available), the Synthchaser Quadra LED slider upgrade kit, as well as a custom modification which routes the external audio input through the Quadra's glorious stereo phase-shifter effect (normally the external input is simply there to mix in an external audio source, and isn't routed through any of the Quadra's processing signal path). For info on the Synthchaser kits, you can read up on them and watch video demos via their website: synthchaser [dot] com.
Additional notes:
(1) the Midi Out can alternately be switched to Midi Thru, via a switch on the board.
(2) I also had my tech install an on/off switch for the LED lights on the sliders, as seen in photo#9, under the "la tosca INC" sticker.
This thing sounds absolutely glorious, and everything, including keyboard aftertouch, is working perfectly. It was fully serviced at the same time as the Synthchaser kits were installed."
"The Prophet 600 is a good synthesizer, but with the GliGli CPU upgrade installed it becomes a great synthesizer! One of the best vintage synth values out there today.
This Prophet 600 is in good working order and has been upgraded with the GliGli mod running the 2.0992 firmware revision (GliGli's final version), a new membrane panel, a new set of Synthchaser key contacts, and a new set of knobs. All 6 voices are tuning, scaling and sounding great.
Very good physical condition, some wear/chips on the side panels (see photos)."
"OBXa in near-mind condition, with Magic Box external midi adapter and custom hard case (orange colour). I say near mint because there's some TINY cosmetic blemishes on the top edge, literally just paint thats been scraped off. No dents, even the paint is still flawless.
many many many hours and $$$ went into restoring the absolute beast of a polysynth. If you think plugins can even come close to this, you've never actually heard one.
-MIDI interface that didnt destroy the case or wood panels ($600USD) ()
-Power supply restored with new capacitors and bridge rectifiers.
-All voice cards completely restored, capacitors (electrolytic and film) replaced, and upgraded with multi turn trimpots.
-Keybed bushings replaced and keys straightened.
-Battery-less storage module installed (synthchaser.com), so no potential for leaky component destroying battery anymore...
Completely calibrated and ready to play. All kinks were ironed out one by one. It is, and I don't say this lightly, the most formidable synth I've ever played.
note - the knob caps are off in some of the pictures for cleaning - they're included :)"
"vintage ARP Pro/DGX Mk. I, aka the Pro Soloist III. This is the model to get! It has the same sounds and fat ladder filter as the Pro Soloist, but with more reliable and more performance friendly pushbutton voice selection switches. This keyboard is the sound of 1970's Genesis.
This synthesizer has just been serviced by Synthchaser, the top ARP specialist - recapped, new key bushings, new LED sliders, new aftertouch sensor, new Synthchaser linear power supply, fully functional, calibrated and sounding great.
Here is a video demo of the actual keyboard being sold"
"This vintage ARP Odyssey has just been fully serviced in October 2023 by Synthchaser, the top ARP specialist - recapped, new key bushings, all new LED sliders, fully functional, tuned and calibrated, and sounding awesome! The Odyssey was ARP's answer to the Minimoog, a feature packed scaled down version of the legendary ARP 2600.
A video functional demonstration of this synth that is for sale is at the end of the pictures list.
The synth is in great condition. This synth comes with illuminated LED sliders that correspond to the colors of the original slider caps. I can disable the illumination for the buyer before shipping, upon request at the time of purchase.
Work just completed on the synth included:
Synthchaser Precision LED slider upgrade - All 34 of the old original sliders have been replaced with new, smooth, high precision LED illuminated sliders. The difference in the way these sliders feel and perform compared to the originals is a huge improvement. LEDs run off their own power supply mounted inside the synth. Illuminated slider caps - Slider caps with a translucent plastic stripe that allows the LED illumination to shine through, while giving you something substantial to grip onto. They look and feel awesome! Power supply rebuilt - All tantalum and electrolytic capacitors in the power supply have been replaced, and high quality, high temperature 105 deg C capacitors have been used for the power supply filter capacitors. All tantalum capacitors replaced - The tantalum capacitors in ARP synths are ticking time bombs.All tantalum capacitors in this synth have been replaced with electrolytics to help provide stable operation for years to come. Synthchaser 4023 Voltage Controlled Filter Submodule - This is a very fat 2 pole dual OTA filter. Synthchaser modules are true to the original designs and professionally built using premium components with superior performance and reliability to those found in the original modules. Keyboard rebuild - New key bushings installed, keys removed and ultrasonically cleaned, bus bars removed and polished, bellcrank caps cleaned and lubricated. Oscilloscope calibration - Calibrated & tuned using oscilloscope and frequency counter. 1/4" output made High - ARPs of this era had an RCA jack as the high output and the 1/4" jack as the low output. As today RCA jacks are an inconvenience for most, the 1/4" jack has been made to a second high output. New rubber feet"
"The ARP Explorer I (Model 2900) was ARP's first non-preset single oscillator synthesizer, pre-dating the Axxe and the Solus. It includes the same 4027-1 Voltage Controlled Oscillator module found in the ARP 2600, and the same 4034 Moog Ladder Filter Voltage Controlled Filter module found in the ARP Pro Soloist. The oscillator is divided down to suboctaves, and shaped into different waveforms (sawtooth, square, pulse, and fuzz) that can be combined simultaneously for an extremely fat sound from a single oscillator synth, particularly in partnership with the ladder filter.
The synth is in good condition, however the silkscreen is very faded as is common for this era ARP synthesizer. This synthesizer was serviced in September 2023 by Synthchaser, and work completed on the synth included:
Synthchaser Precision slider upgrade - All 12 of the old original sliders have been replaced with new, smooth, high precision sliders. The difference in the way these sliders feel and perform compared to the originals is a huge improvement. The original style slider caps are fitted to keep the look original. Power supply recapped - All tantalum and electrolytic capacitors in the power supply have been replaced, and high quality, high temperature 105 deg C capacitors have been used for the power supply filter capacitors. Tantalum capacitors replaced - The tantalum capacitors in ARP synths are ticking time bombs. All tantalum capacitors in this synth (except those in the sub-modules) have been replaced with electrolytics to help provide stable operation for years to come. Keyboard rebuild - New key bushings installed, keys removed and ultrasonically cleaned, bus bars removed and polished, key contacts cleaned and adjusted. Oscilloscope calibration - Calibrated & tuned using oscilloscope and frequency counter. 1/4" output made High - ARPs of this era had an RCA jack as the high output and the 1/4" jack as the low output. As today RCA jacks are an inconvenience for most, the 1/4" jack has been made to a second high output. This modification is easily reversible by cutting 1 wire."
