Showing posts with label CHD ELEKTROSERVIS. Show all posts
Showing posts with label CHD ELEKTROSERVIS. Show all posts

Wednesday, July 14, 2021


via this auction

"Work list (Excerpt):

Change all elec. caps and opamps,
New transistors and opamp installed on power supply board.
Change transistors in DAC part and opamps on CV route on key assigner board with new ones.
New "spark-killer" capacitor installed (relocated on power switch pins).
Keys knobs, switches and jacks cleaning.
CHD MIDI installed.

Sunday, May 09, 2021


video by Mindburner

"This classic Roland has become even more useable with this CHD electronics MIDI kit. Here I detail the install and show the insides of the synth"

Monday, December 16, 2019

Korg Mono/Poly w/ CHD MIDI

via this auction

Monday, April 16, 2018

Korg Polysix Vintage Analog Synthesizer w/ MIDI SN 385503

via this auction

"It is in superb shape for it's age and has none of the issues commonly found on ailing/unkempt P6s; the CPU board has a replacement coin battery holder with no leak prior battery leak damage. All the voices sound vibrant and full. This synth also has a CHD MIDI kit installed for playing the Polysix from an outside MIDI source (Ableton, external sequencer, etc). All of the keys trigger fine."

Saturday, January 21, 2017


CHD has gone eurorack. You can see some of their previous products here.

via this auction

Tunable Noise + S&H Generator is designed for Eurorack modular synthesizer systems.
Noise tunable from white noise, through pink noise up to digital harsh sound.
The tuning is not based on usual filtering - special circuit is used.
Noise spectrum is controllable manually or by external CV source (e.g. keyboard, envelope generator, LFO, sequencer, etc.).
Noise spectrum can be modulated by external (LFO) or internal source (noise itself or Sample&Hold generator).
Independent Sample&Hold generator with external clock input.
Stainless steel front panel.
Pure analogue circuitry (no DSP technology is used).
Fully hand-made - each module is tested and adjusted individually.

Sunday, December 04, 2016

Roland TR-808 Vintage Analog Drum Machine w/MIDI

via this auction

"Listing is for a Roland TR-808 Drum Machine with CHD MIDI retrofit! I used this solely as a MIDI triggered sound source as DIN sync does not appear to function and when syncing the internal sequencer to MIDI, it syncs fine when in "pattern write" mode but is slightly delayed when in 'manual play' mode. For these reasons, the purchaser should plan on using it as a MIDI triggered unit for getting authentic TR-808 sounds. Samples, VST instruments, clones, etc. cannot touch the sound of the real thing."

Wednesday, November 30, 2016

Korg Mono/Poly w/ CHD ELEKTROSERVIS MP-KBD MIDI Interface Kit

via this auction

Saturday, November 19, 2016

Roland Jupiter-4 JP-4 Analog Synthesizer w/ MIDI

via this auction

"This Jupiter 4 is in good cosmetic condition and 100% functional. It has been serviced top to bottom and needs nothing. During service a MIDI retrofit was added to give this unit some modern control features...

MIDI: There is a CHD ElectroServis MIDI kit installed."

Monday, July 20, 2015


via this auction

Details on the MIDI kit via CHD:

"P6-KBD MIDI retrofit enables Korg Polysix to be controlled via MIDI. You can remotely control the keyboard and speed of the arpeggiator by MIDI commands. The instrument works like polyphonic MIDI sound expander.


The instrument's keyboard is controlled manually and by MIDI Note On/Off commands simultaneously.
The keyboard can be transposed in whole range of MIDI notes 0~127.
Four modes of key priority can be chosen: Last / Higher / Lower / None.
The instrument's tone generators can be detuned (in semitone steps) by MIDI Pitch Bend command. The bend range is from 0 to ±24 semitones.
Any receiving MIDI channel or OMNI mode can be selected via SysEx message.
Arpeggiator can be synchronized with internal instrument's tempo generator or with external MIDI clock.
All original features of the instrument are not changed and it can be used the same way as before the interface installation.
Installation of interface into the instrument is very easy.
The product is covered by thirty months warranty - more info
Parameters adjustable by user:

MIDI Channel (1 to 16 / OMNI)
Key Shift (+0 to +67 semitones)
Key Priority (Last / Higher / Lower / None)
Pitch Bend (Wheel) Range (from +-0 to +-24 semitones)
Arpg Clock Rate (internal or 1~128 MIDI ticks)
MIDI implementation - receive only:

Note On / Off (0~127)
CC 16 - Key Shift parameter setting (0~127)
CC 17 - Key Priority parameter setting (0~127)
CC 18 - Pitch Wheel Range parameter setting (0~127)
CC 19 - Arpg Clock Rate parameter setting (0~127)
CC 64 - Hold
CC 120 - ASO
CC 121 - RAC
CC 123 - ANO
Pitch Wheel (0~16383)
System Clock
System Exclusive - setting of all parameters and selection of MIDI channel (1~16 / OMNI)"

Friday, May 23, 2014

CHD PGM CR 78 Programmer for Roland CR 78 CompuRhythm

via this auction

"Very useful and rare tool to programm the CR 78."

Thursday, April 10, 2014

Roland TR808 Drum Machine with CHD MIDI

via this auction

Sunday, January 12, 2014

KORG Mono/Poly Analog Synth w CHD MIDI Retrofit

via this auction

Monday, January 07, 2013


via this auction
This is the one in this video.

"Roland TR-808 that has been professionally upgraded with an internal MIDI interface! No bulky ugly outboard MIDI interface box with a nasty wall wart power supply. The MIDI interface installed is simply tacked onto the circuit. There has been no invasive cutting of the circuit board, and if you want to, the MIDI interface can be easily removed and the drum machine can be set right back to stock condition. The MIDI instalation was completely non-destructive. Look at the pictures to see what the interface looks like. Included is the original switch with it's cable if you want to set it back to stock...

"This tr-808 sounds excellent, and with the built in MIDI interface it is easier than ever to sync up to a computer. I have been syncing it up to Ableton Live and it is rock solid, and sounds so good. The sync switch has been replaced with a three position switch, and all you have to do is set it to the middle position for MIDI to be implemented. It's very easy to turn MIDI on. With the MIDI interface you can start/stop the internal sequencer of the tr-808 from your computer sequencer, AND you can trigger all the individual sounds on a keyboard at the same time while it's running! You can also use the TR-808 as a sound module if you don't want to use it's built in sequencer. If you want to use the TR-808 in DIN sync mode all you have to do is simply switch it to input or output in the back. This is by far the best MIDI interface available for the TR-808, and it has been very well engineered. You can change the MIDI parameters through SYSEX commands, and it is easy to do. Included are all the MIDI manuals, a CD along with a MIDI cable that came with the kit...

MIDI kit link"

Pics of the inside below.

Sunday, April 08, 2012

RARE Elektroservis Roland CR-78 Programmer/Sync/Controller CR78-PGM

via this auction

"Up for auction is a VERY RARE complete controller/sync/programmer for Roland CR-78 Drum Machines. This was made by Elektroservis in Europe in 2009/10 (they are leader in analog interfaces) but this unit is now discontinued an almost impossible to find new or used.

Allows you to sync your CR-78 to midi clock in your DAW, and also offers complete programming control of the CR-78. In 100% operational condtion, I am the original owner and only used this unit for a few hours. There is one small scratch on the face of the unit, otherwise pristine.

Comes with operating manual, and US AC adapter.

Visit for more information.

I am also selling my pristine CR-78 in a separate auction. Check my other auctions!"

Sunday, October 24, 2010

Monopoly with polymidi sequenced from Ableton

YouTube via fuckingharpsichord | October 24, 2010

"So now my Monopoly owns a polyphonic midi-retrofit from CHD Elektroservis. 808 beat is done in Ableton. Theres a little delay on the sound because the sound you hear is the actual tape recording and plays a little slower then thza original sound. Not really special but I just wanted to show this monophonic midicontrolled polysynth."

Monday, March 02, 2009

tr-808 controlled by ableton = shuffle

YouTube via pac209
"CHD Elektroservis MIDI interface installed -
with this interface, midi clock and note commands with velocity can be received, the Sync I/O function is maintained (everything like original state) and no extra holes have to be drilled in the case"

Thursday, February 19, 2009


"CR78-PGM is programmer and controller for Roland CR-78 drummachine. With help of it, CR-78 can be programmed very easy (by similar way as with original Roland WS-1 programmer). More over, CR78-PGM enables to control CR-78 during playback manually or via MIRI or DIN-SYNC buses.

1. Display (LCD)
2. Rotary encoder
5. START/STOP signal output
6. WRITE signal output
7. CLOCK signal output
8. DIN-SYNC bus input
9. Synchronization selector
10. MIDI bus input
11. Working mode selector
12. LCD contrast setting
13. Supply connector"

You can find more info on CHD ELEKTROSERVIS

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

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