A-190 +Hold +Shuffle

Classic A-190 + Shufflebox DIY kit = Swing and quantized Start/Stop

Combination of the classic Doepfer MIDI interface A-190 (or A-190-1) which is deprecated, but might be available on ebay, and the DIY kit shufflebox from frequencyresponse:
http://frequencyresponse.ch/?p=shufflebox

The button allows to stop, or start the clock for the A-100 system against a steady external MIDI master clock, each action delayed to the next bar (always assuming 4/4 time signature). The poti allows to shuffle the clock. All non-clock MIDI messages pass through to the A-190. It works very well.

Requires MIDI sockets in the case. MIDI In from case goes into MIDI In from shufflebox, MIDI Out from shufflebox goes to MIDI In of the A-190, A-190 MIDI Out goes to the cases MIDI out socket. You may want to use coupling jacks between the modified module and the case terminals so that moving the module is still possible – one DIN 5 pin 180° connection using all contacts (=non-standard) does the job.

The modification icludes these steps:

• Unsolder MIDI sockets from A-190.
• Cut shufflebox circuit board to match eurorack height. The MIDI / DIN Sync input selector of the shufflebox is on the removed part. It must be bridged in MIDI position on the remaining part of the circuit board.
• Solder remaining shufflebox kit (everything except sockets and switch).
• To piggyback the shufflebox to the A-190 you need to drill one hole in the shufflebox circuit board (the other original hole was on the part which is cut away, but its easy to find a suitable spot).
• I placed the shufflebox LED close to the A-190 buttons which have plenty of space to let the light shine through. You could also put the LED in the front plate of the A-190 if you don't mind the additional flashing.
• I used a heavy "vandalism proof" trigger switch in the right size for the existing A-190 MIDI port hole, and a 17mm aluminum poti cap, both from reichelt.de. The poti can be centered using a washer of matching size. The result feels very solid.