Jacob Korn

Roland TR-909 tune+decay mods, firmware upgrade

Posted by in equipment, mods & repairs, News, Studio

Duration 6h for Mods + OS update: 300€ +Parts (EPROM) and postage (german clients +19%) Modded this little Roland TR-909 together with Claudio of discrete-audio-solutions back in the days. All mods are switchable to „stock“ sound (except clap noise). Mods: -BD-Tune, BD-Overdrive, BD-Decay Range Extension Switch -Clap Noise Volume -Rimshot Pitch variations switch -Hihat Tune Also exchanged the eprom to the latest firmware (V4) with stable MIDI timing. Thanks to curetronic for the steady desoldering-hand:) www.discrete-audio-solutions.com www.curetronic.com http://colinfraser.com/tr909/909mods/909mods.htm


Korg Polysix repair+mod+MIDI

Posted by in mods & repairs, News

Got this baby in very bad nonworking condition. Had to replace the processor board (battery leakage) with a cloned version and to source 12 new SSM chips. It got also MIDI plus an input for using the internal chorus FX now. After cleaning its looking brand new. A nice 5k pot replacing R116 near IC31 will increase the unison detune! http://synthhacker.blogspot.de/2013/04/polysix-adding-detune.html Thx so much to Curetronic.com and Malte Rogacki for helping with the reanimation:)


Vermona Piano Strings Chorus+EQ input mod

Posted by in mods & repairs, News

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. 


Yamaha E-75 Son Of GX modification

Posted by in mods & repairs, Studio

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