This 80ies east german keyboard features a true 3 line BBD chorus section by the likes of solina and logan plus a 3 band eq that is accessible now via jack. Look for Mod 1-3 in section ST2. Thanks to vermona and Lutz Würker for sending the schematics. Time: 30min.
Knock on wood:) Rumburack Knit Rider triggers vintage Roland Drummachine with inverted positive triggers using Quattro Figaro. Clock out was used to sync to TR-77 preset rhythms. Mods by Jacob Korn. www.bastl-instruments.com
Got this organ with guts from the infamous GX-1 and the CS80. After the modification we got full access to the 2 polysynths (7 voices 2 OSC and LP+HP filter each) and the monophonic bass synth. 3 times 16 controls in total: 4 Filter controls (Low pass filter frequency, Low resonance, High pass filter frequency, High pass resonance) 5 stage Filter Envelope Generator (Initial Level, Attack level, Attack, Decay, Release) 4 stage Voltage Controlled Amplifier Envelope Generator (Attack, Decay, Release, Sustain) 3 waveforms possible for use in parallel (saw, square, narrow pulse) CV-control for…read more
Oberheim Matrix 1000 EPROM chip, operating system version 1.16. The last official version released by Oberheim was 1.11; this version corrects some MIDI SysEx control issues that Oberheim overlooked, such as a really slow response to filter cutoff frequency settings. This replaces chip U804 on the main board (it is socketed, so no soldering is required). Took about 30min. – Bug fixes made by Nordcore. – MIDI NRPN parameters editing fix. – Faster processing of parameter changes that need a modulation matrix rebuild, there’s still a small lag but it’s…read more
This one was suffering from juno cancer on one voice. Uncoating the 80017 chip did partially not work (no resonance). Put a replacement chip on a socket and recalibrated all of the 6 voices. Took 2-3h For the chorus there was used a test-point on the board as input and a new pot was installed for chorus speed. Very useful! 1-2h
Duration 3h for Mods: 150€ + parts (housing, knobs) + postage (german clients + 19% tax) Got this defective, rewired some loose ribbon cables and exchanged the HH-slider. Mods are CH+OH+Ride decays and tune for ride (40106 clock not too stable). Maybe replacing it with an LTC. Thx to www.discrete-audio-solutions.com for the parts. More info here: http://electro-music.com/forum/topic-37316.html
The usual 80017chip fail aka Juno cancer on 4 voices. The bass voice was exchanged before but faulty again. Removed coating, installed sockets, test and calibration done. Nice tuned juno 106 and TR-707 in 2HE rackformat. 5hours.