MIDI CPU: A DIY MIDI Controller for Everyone

Organists, guitarists, synthesists, DJs and experimenters continue to create unique DIY MIDI controllers using the MIDI CPU. Explore the MIDI CPU forum to find strategies for generating MIDI output from ribbon controllers, breath sensors, foot switches, organ bass pedals, second touch organ manuals, joysticks, accordions, 128-switch pushbutton arrays, light detectors, Hall effect sensors, piezo elements, and lasers.

Have you joined the forum to discuss your DIY MIDI project idea?

Here are some recent highlights from the forum:

VFXcompositor’s concept for a “next level MIDI performance controller”:

DIY MIDI bass pedal projects from Robrolley and ham hands:

Korg Radias foot switch controller by michaelh:



DIY 10x MIDI Thru Box

Pete Brown at 10rem.net is building a custom 10x MIDI Thru box based on the 5x MIDI Thru circuit available at the Highly Liquid library.

To date, Pete has written 5 detailed blog posts for the ongoing project:

Potentially useful information for those attempting a MIDI project or DIY circuit board design.

Tim Laursen’s Robot Drum Creation

Tim Laursen combined a power supply, drum machine, mixer, MSA-R MIDI decoder, Darlington drivers, and a collection of individually miked, solenoid-actuated drums.  The result is “Double Rainbow”, a complete mobile robot drum system.

Some technical details can be found in this forum thread.  Tim’s work also appears in this video from Sequence of Waves.

Howto: Build a Cigar Box MIDI Controller for Max/MSP

The previous howto described the process of making a jumbo-sized MIDI controller. In this howto, the MIDI CPU is used to make a more compact device: a cigar box MIDI controller that can control Max/MSP (and any other MIDI software or hardware).

Here are the basic steps:

  1. Select a suitable cigar box.
  2. Select the control hardware.
  3. Design the cutouts for the top & back panels.
  4. Cut the cigar box with a laser cutter.
  5. Create the MIDI CPU wiring diagram.
  6. Mount and wire the controls.
  7. Configure the MIDI CPU.
  8. Connect the completed controller to a computer running Max.

This zip file includes the parts list (Open Office .ods), design drawings (Corel Draw .cdr & .png) and MIDI SysEx files (.txt and binary .syx) used in the project. Discuss this howto at the forums.

Continue reading Howto: Build a Cigar Box MIDI Controller for Max/MSP

“Living Schematic” MIDI CPU Demo at CIF Open House

As of January 2011, Highly Liquid has moved into a studio at Columbus Idea Foundry, a rapidly growing hacker/art space and community workshop.

Guests at Saturday’s CIF open house encountered this:

The front wall of the studio is painted with an oversize MIDI CPU wiring diagram, similar to those posted at the MIDI CPU support forum.  Actual controls (29 buttons, two knobs, and a photoresistor) have been mounted on the corresponding schematic symbols (switches, potentiometers, and variable resistor).

Inside the studio, the controls are wired to a MIDI CPU as shown by the diagram.  MIDI output from the MIDI CPU drives a Korg Electribe-R and Roland MT-32.  The resulting audio signals are mixed, amplified, and routed to overhead speakers–completing the interactive “loop”.

Visitors generated a variety of musical sounds by experimenting with the controls.

Technical details of the project have been posted here.

Photos by Amy Glass

Update–YouTube video:

Build Your Own Guitar Pedal Switcher

Mel at Wabbit Wanch Design combined an MSA-R MIDI decoder, DPDT relays, and a rackmount enclosure to build the “iPatch”: an 8-channel guitar pedal switcher.  Thanks to the MSA, the switcher can respond to MIDI program, CC, or note commands for preset recall or individual loop control.

Mel provided details and photos in his write-up at the Highly Liquid Forums.

Have you joined the forums yet?