GumiElectronic

Some weeks or months or years ago 477 contacted me with questions about bending his R-100. He recently finished the project and the result is gorgeous. He installed the U24 and U40 bends opting for a built-in patchbay as opposed to a breakout box or toggles. All 12 pins of U40 are patchable. 477 (aka […]

If your R-100 is suddenly confused and misbehaving, the factory reset procedures might knock the sense back into it. I found this info in this circuitbenders thread. It was originally written in French. Here is my translation with help from Google Translator: “To initialize the parameters only: hold down the [ERASE] button while you turn […]

Here are a couple pics of the ROM switcher that came installed in my R-100. Apparently there were different versions of these boards, as seen on the Burnkit2600 R-100 page. Mine is labeled as an R-50 Soundswitcher by Drumware Inc. and it has an additional 2-4 Line Decoder IC, but I’m not sure what purpose […]

Here are the voices of CP-2 and CP-3 (optional R-100 voice ROMs) with their respective pad assignments. CP-2 Pad 1: Atomic Kick/Room Kick/Acoustic Kick Pad 2: Atomic Snare/Room Snare/Acoustic Snare Pad 3: Electronic Tom Hi/Purple Rim Shot/Click Pad 4: Electronic Tom Mid/Claps/Funk Bass Pad 5: Electronic Tom Low/Mellow Bass/Electronic Snare Pad 6: Closed Hi-Hat/Open Hi-Hat/Tympani […]

You can get a variety of nasty distortion/bit reduction effects by connecting pins 1–12 on U40, which is the R-100’s DAC chip. I tested all 12 pins, but I only ended up wiring pins 1–8 to a bank of switches on the R-100’s front panel. These bends turn the R-100 into a very dirty beast.

Photos of the Kawai R-100 in various stages of bending.

Download the Kawai R-100 Service Manual: It’s certainly not as detailed as some service notes, but it’s enough to get you started. You might want to take a peek at the schematic before doing any mods to U24 (the voice ROM IC). Note that there appear to be some discrepancies between the component numbers shown […]

The buttons on my R-100 were rather fussy. Sometimes they required multiple presses and other times they’d trigger several times upon a single press, so it was frustrating to program the machine. But I was able to clean them and now they work like new. Here are the materials I used: • miniature flat-head screw […]

The main R-100 modifications are centered on U24*, which is the voice ROM IC. All you need to do is connect various pins on U24 to get a variety of nasty sounds, everything from rippling ring modulation to crunchy distortion to stuttering delay-like effects. The trick is figuring out which pins can be connected without […]