MATRIXSYNTH: synth guts

Showing posts with label synth guts. Show all posts
Showing posts with label synth guts. Show all posts

Sunday, September 03, 2023

PAIA 2700 4700 8700 MODULAR DIY Analog Synthesizer Parts

via this auction

Monday, August 28, 2023

Sequential Circuits Prophet 2002 Vintage Rack Mount Digital Sampler SN 0274 w/ Original Manual

via this auction

Pic of the inside below.

The Massive Sound Of An Experimental Soviet Drum Machine

video upload by HAINBACH

This appears to be the first post to feature the RMIF ES-2-5.

"The RMIF ES-2-5 is an experimental drum machine that was made in Riga, Latvia, in the last days of the Soviet Union (1991). It was an attempt at re-creating the Roland TR-808, but was hampered by the lack of microchip technology available. RMIF abandoned the project after only a testing run of 30 units where made. One rare surviving example found its way to my studio in a sorry state. I had it restored to better then new condition, as I feel it is a piece of instrument history. And it sounds so very very heavy and melancholic.

PATRONS get sounds of the ES-2-5:"

00:00 Unboxing
01:08 First Track: With Maestro
02:30 Second Track: Solo ES-2-5
03:27 A Closer Look
05:31 Third Track: FX
06:22 The Sequencer
07:41 History Time
09:16 The Competition At The Time
09:50 Relevance Today

Sunday, August 27, 2023

VINTAGE Moog Minimoog MODEL D “Oscillator Board“

via this auction

Prophet VS in for a major service

video upload by Espen Kraft

"I finally gave the VS some TLC. It's been sitting there unused for quite some time due to very glitchy buttons, a almost unreadable display and a PSU that was on it's last dying breath.
A new PSU, new display, a new set of switches were among my priorities leaving this with my tech.

I wearing a t-shirt from

The power supply that's been installed can be found here:

The rest of the new components can be found with the help of Google. ;-)

A big thanks to the tech Trond Gribbestad Lund for good work, and to Anders Jensen for taking a Saturday off to shoot the tech at work. Thanks guys!"

Tuesday, August 22, 2023

Rob Rosen Reveals His Ultimate Synth Collection

video upload by Anthony Marinelli Music

A look inside the Yamaha CS80, the 14th ever made Sequential Prophet-5, a Rev 1, and a Roland Juno-106, touching on some of the evolution of analog synthesis technology over the years.

"I hope you enjoy this rare opportunity to visit with my close friend Rob Rosen for a deep dive into his ultimate vintage synth collection. Together, we’ll see inside some of the rarest synthesizers of all-time and learn from this master technician how synthesizers have evolved, what makes them tick and why synthesizers make such cool sounds!

I consider Rob’s shop @Rosen Sound ground zero for anything relating to synthesizers. It’s also the biggest wonderland of vintage synths in perfect working order that you’ll ever see .

Rob is a self-taught technician and is now the world leader for repair, restoration, custom manufacturing and sales of vintage synthesizers. He’s also quite an accomplished musician programmer and keyboard player as well."

Chapter Time Stamps:
00:00:01 Intro Anthony on the street in Burbank, CA
00:01:55 Entering Inside Rosen Sound
00:02:06 Meeting “P” from Chromeo and The Rosen Sound Team
00:03:06 Rob shows us his personal work space
00:11:42 Montage of Synths - Start
00:12:35 Montage of Synths - End
00:12:36 Anthony and Rob in “The Cabin” - a wonderland of vintage synths
00:13:42 Anthony explains and demonstrates features on the CS-80
00:20:36 CS-80 “Under the Hood” in-depth tour by Rob
00:53:31 Prophet 5 “Under the Hood” in-depth tour by Rob
01:12:50 Anthony Demonstrates some of the Juno 106 sounds
01:19:27 Juno-106 “Under the Hood” in-depth tour by Rob
01:28:54 One-of-a-Kind Oberheim Modular 8 Voice System tour by Rob
01:35:31 Anthony asks Rob 20 Questions about Synthesizers
01:39:09 Rob asks Anthony some Questions about Synthesizers
01:49:47 Bass Shootout: 1973 Moog System 55 VS ARP 2600
01:54:54 Shoot Out Conclusion and Bass Tips

Saturday, August 19, 2023

Arp AXXE LED fader replacements! #synthesizer #vintagesynth #arp

video upload by Zed AudioLab

"New led slider pots for my Arp AXXE using my new bourns to cts slider PCB conversion boards :)"

Wednesday, August 16, 2023

How To Properly Calibrate Your Minimoog Oscillators (by synthpro)

video upload by synthpro

"This is a video that I have had a request to make for some time now.
In this video I show you how to calibrate minimoogs with the version 2 oscillator board.

This video will also work for calibrating the Behringer D since it uses the same version 2 oscillator design.

NOTE: Calibration for the version 3 oscillator board is much different.

If this video helped you out and you would like to make a donation,
My paypal address is:

Thanks for watching and hope this helps you!


Tuesday, August 15, 2023

Why The Finicky Analog Prophet 10 is Better Than Digital Keyboards

video upload by Retrothusiast

"The Prophet 10 is a wonderful analog synthesizer. However, from tuning issues to dropped notes, there were a few bumps in the road to reach my destination. Follow me on my journey as I explore this amazing instrument!

0:00 Intro
0:44 Want the Real Thing
1:16 Prophet 10 Specs
2:01 Prophet 10 Sound Demo
3:37 Tuning Issues & Dropped Notes
4:37 Prophet 10 Board Replacement
4:55 How To Turn On A Prophet
6:58 Afterglow

Watch Alex Ball tell the story of the Prophet: [posted here]

Watch me replace the Prophet 10 main board:"

Replacing the Main Board in a Sequential Prophet 5/10

video upload by Retrothusiast

"I had to replace the main board in my Sequential Prophet 10 because when the Rev 1/2 filters were selected, some of the notes would drop out. This is, however, after I had already replaced this keyboard because my first keyboard would not stay in tune. I'll be posting another video touching on this in the near future.

Sequential sent me new boards and I recorded a quick, down and dirty video documenting the procedure for anyone else who might have to replace their boards and wanted to see what's involved.

I followed these instructions provided by Sequential Support:

Hats off to Sequential Support. This company really is top-notch and despite the issues I had with the hardware, I can tell the Sequential team really cares and is extremely helpful and supportive! Thank you, Sequential!"

Thursday, August 10, 2023

Oberheim OB-X Mono Synth - 10 Note Sequence

video upload by Polydata

"The Korg SQ-64 sending a repeating 10-note pattern to the single card OB-X project I built from @RosenSound"

That's one voice board of the OB-X. Interesting concept that could be applied to other synth voice boards. Definitely want to keep a soft brush duster around, or a clear decksaver type cover might work. It would be kind of cool to know/imagine the electricy flowing through the components while playing.

Tuesday, August 08, 2023

ONDIOLINE Quick Oscillator Repair Job using Forgotten Futures Book

video upload by Vintage Keys Studio

"A brief explanation of an oscillator fault in the Ondioline. Resistors around the Oscillator valve (an ECC82) were all original and some had failed, causing a rise in pitch whenever a note was played.

Filmed and Badly Edited on a phone by Steve Christie, as Louisa was away on holiday. Steve hasn't had a holiday for 10 years.



See the Ondioline label below for more. Also checke out Jean-Jacques Perrey et son Ondioline.

PE Clef String Ensemble 1978 Custom Kit-Built Analog Synth with mods

video upload by Vintage Keys Studio

PE = Practical Electronics. This is the first post to feature a demo of the Clef String Ensemble. You find a couple of pics of one in this post from 2012.

"Steve Christie (aka whatever silly-sounding name he makes up) demonstrates the PE Clef String Ensemble from 1978. With added functionality with a few simple modifications.

Here are the original plans for your perusal:

Filmed and Edited by Louisa Revolta
Recorded and Mixed by Steve Christie at Vintage Keys Studio"

Monday, August 07, 2023

Roland Juno-106 61-Key Programmable Polyphonic Synthesizer SN 406619

via this auction

Pics of the inside below.

"Due for original voice chip cleaning or replacement which is normal for these classics and also reflected in the price and condition of “fair.” Two of its voices are out: VCAs 2 and 4. Meaning the synth works in all ways but skips those voices when playing in poly mode. Unison mode sounds great, of course. But anyway you probably know the drill with these 106 voice chips. You can give the chips a bath in acetone and hope for the best or replace at ~$50 each. Replacement of all the chips at once seems to be the more convenient option, you usually get a discount for buying all six, and it is a permanent solution. I like doubleheart audio because they'll do the work for you and calibrate as well when you send them the motherboard. Estimated cost of chip replacement is $250 DIY to 300+ for full service."

Wednesday, August 02, 2023

1981 Vintage EKO Bass Pedal K3 Monophonic Analog Synth SN 0626

via this auction

Pics of the inside below.

Monday, July 31, 2023

Sequential Circuits Prophet VS - Serviced W/16bank Memory Cart & FlightCase

via this auction

Pics of the inside below.

The synth was serviced a couple of years ago and has seen little use since while It stays covered in a clean studio. All buttons and display are new and the CEM 5530 chips which are known to fail have been replaced with the infamous Straylight Engineering clones. The 1.3 "Shalebridge" OS was installed and battery recently checked good at 3.05v. All keys, joystick, knobs, wheels, jacks work great. The aftertouch still works, which is rare for this model but you have to press with some force and the synth needs to be resting on a flat surface as recommended by Sequential. There are some blemishes on the side panels as seen in the image highlighted by the sunlight but in reality it's minor and the face/panel looks great. It's been very reliable for me over the years and is a pleasure to play. A power cord and manual are included plus an amazing 16 bank cart full of sound banks including all of the originals. Comes with a custom fit case that could use some new foam but will protect the synth as it will be carefully packed in the case and then boxed/packed again."

Thursday, July 20, 2023

USSR 80's Mini Moog Clone Built In Now Ukraine - ESTRADIN 230

video upload by LOOK MUM NO COMPUTER

"THE USSR ESTRADIN 230 Synthesizer, built in now ukraine.

download sounds from this synth to use, here :-"

Monday, July 17, 2023

E-MU Systems Emulator III 61-Key 16-Voice Sampler Workstation w/ Spare Cards SN 0380143

via this auction

"This is the FULL 8MB version and all 16 voices work 100%!

This keyboard has been painstakingly repaired and restored, with a new OLED display, ALL NEW buttons (switches and caps) and faders, ALL NEW LEDs, and ALL NEW internal ribbon cables and connectors, and new quiet cooling fans with internal thermostats.

Not only do you get the above repairs, I have replaced the internal SCSI hard drive with a SCSI Compact Flash emulator (internal) as well as an external CF reader. I AM ALSO INCLUDING ALL EMU SYSTEMS CD-ROM BANKS FOR EIII, ready to load. on CF cards, which I painstakingly transferred from the original CD-ROMs.

Included in this sale:

E-Mu Systems Emulator III Digital Sampler/Workstation with 8MB RAM
Internal CF reader with fixed (internal) 1GB boot/storage bank
External (Floppy drive slot) CF PCMCIA card reader
New OLED display
All new tact switches (buttons) and caps
All new LEDs
All new internal ribbon cables and power cables
VHS Instructional Videos
E-III Manuals (two binders)
8 CF CARDS containing original E-Mu CD-ROM Library for EIII, plus "DM Sample Bank".
Complete set of spare cards (Digital, DAC, ADC, RAM with 4MB RAM and NO CEM chips).
One complete "Card Cage" (internal backplane, mother board and card-holder).
One original EIII (spare) PSU
This Sampler contains 16 CEM 3387 analog filters which give the samples this amazing clarity and depth. The all CLASS A internal circuitry cannot be matched these days and the sound the comes from this sampler is BIG. Supports SMPTE time code, MIDI, SCSI, as well as 16 (!) individual outputs as 1/4" jacks, in addition to Stereo out."

Sunday, July 16, 2023

Korg PS-3100 Its Alive!

via this auction

Pics of the inside below.

"Aesthetic condition 7/10

Electronically 90%

Functionality 65%


The instrument turns on and makes sound. Keybed is working via the trigger output fully and trigger all notes, however some note behave differently and randomly. This most likely cause by the cracked pcd slots, which is a n issue with most ps-series synths. I recommend you take a look at the youtube video.

Wave forms, vco, is working and can select pulse, saw, noise etc. Other functions seem to be functioning correctly via the eg output. Also all other functions on the control panel seems to be working as it should.

Buttons and knobs are working, but need work or replacement as there is some crackle and noticeable hiccup especially with the switches and selectors. This probably needs cleaning or replacement.

Originally when i bought this synth it did not turn on, so I asked the tech to change all the capacitors (about 100) to see if it will turn on and make sound safely.

As mentioned above, the pcb slots are cracked and need replacement. There is a 80% chance that after replacing these slots, the synth will work properly but i will leave that judgement to a pro.

Also some retracing or treatment need to be done, due to corrosion (10%). I have more photo's and video's available, a drive link can be shared to see."

Saturday, July 15, 2023

1970s Moog MKG Ten Band Graphic Equalizer

videos uploaded by Cfpp0

Update: quick demos of the unit added.

"I got carried away and forgot to gain stage throughout, but you get the idea. On sale at Christopher’s Boutique 489 ("

via this auction

You can find one featured in this video.

"This is a 1970s Moog MKG 10 band graphic equalizer. Sometimes people disparage graphic equalizers in favor of parametric equalizers. Some people say graphic equalizers are for killing microphone feedback in live rooms, or cutting an unruly resonance in that live room. True, graphic equalizers focus on specific bands, but the shape makes a difference, and Moog knew what they were doing back in 1970s.

We’ve had this for a while and have used it mostly on things like our Roland TR 606 or our Korg MS-20. For the 606, raising the 2k band way up and the 4k up a bit, while dipping the 8k band can make those famous hi hats pop with more presence and less shrill. 63 makes the kick thump. For other things, like synths, I’d just boost the 31 or 63 Hz band to pump it up, warm it up, round it off.

The ears are ingenious. This whole line—the phase shifter, the parametric, this graphic—have reversible ears. Orient them one way and you can rackmount it in any 19” rack. Orient them the other way and you have handles that are cleaner to look at when used desktop-style.

The sliders have an indentation at 0, so you can always feel and find your way back to null.

It sounds great and there is no scratchiness. The only issue is the 1k band, which sometimes glitches at the very top or very bottom of the slider. When we got this it was filthy. I cleaned the grooves within the ears, as there was crud in them. I cleaned grime out of the slider tracts. And dusted the inside. I sprayed the 1k band with deo it, which improved the 1k band’s performance a bit, but if you are buying this to do fancy live wiggling of sliders, maybe get another one—or buy a fixed filter bank. I’d recommend this more for someone who needs it for seeking a sound, accentuating certain frequencies, or doing weird bandpass-ish comb-ish stuff. That said, they’re all perfect except the 1k. The 250 is the stiffest, the rest are smooth."

Pic of the inside.

Friday, July 14, 2023

Ensoniq ESQ-1 Wave Synthesizer - w/ LED Sliders

via this auction

Pics of the inside below.

"This ESQ-1 has been completely overhauled and restored and features upgraded LED sliders. It includes an original Ensoniq ESQ-1 E2 PROM Storage Cartridge.

You're not likely to find another ESQ-1 for sale like this one any time soon. Yes, you might see so-called "professionally refurbished" synths out there, but none like this.

There were no compromises when it came to restoring this ESQ-1. However, I did not attempt to restore this ESQ-1 cosmetically, so there are nicks, light scratches, and other signs of age and use. Read on to see what was done:


This ESQ-1 has been completely stripped down, literally every part removed and thoroughly cleaned by hand.

For the body, buttons, and keys, I used hot, soapy water, brushes, cloths, and towels to remove all gunk and nastiness that built up over the years.

Every key was removed, cleaned, and if there were chips or holes they were filled and repaired.

The wires and contacts along the keybed were all cleaned and adjusted where necessary.

Every body part was removed and cleaned as described above - no body part was left in place before cleaning.

Each button was removed and cleaned, along with the display cover.

Old flux and grime and dust were all cleaned off the PCBs using appropriate solvents and cleaners. The jacks were all cleaned out. The cartridge port contacts were cleaned.

The pitch and mod wheels and mounting hardware were removed, scrubbed, and cleaned.


Patch n Tweak
Switched On Make Synthesizer Evolution Vintage Synthesizers Creating Sound Fundlementals of Synthesizer Programming Kraftwerk

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