DIY 10x MIDI Thru Box

Pete Brown at 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.

MIDI CPU: Instant DIY MIDI Controller

The new MIDI CPU accepts input from switches, potentiometers, rotary encoders, switch matrices and external digital & analog signals.  In response, it generates virtually any type of MIDI message.  Buy now!

The MIDI CPU ships fully assembled.  Simply attach MIDI connectors, control components, and a battery or DC power supply.

Features include:

  • 24 independent input terminals
  • Monitors up to 128 switches, 14 potentiometers, or 12 encoders
  • Allows mixed input types
  • Merges MIDI input with locally generated messages—multiple units share a single MIDI Out port
  • Powered via battery or DC supply between 3.3V and 12V
  • Measures only 66mm x 38mm (2.6″ x 1.5″)
  • Configured via MIDI SysEx message
  • User-upgradeable firmware

The MIDI CPU has a long list of potential applications.  Build your own traditional footswitch, keyboard, or “knob box” controller.  Build your own alternative MIDI controller—optical theremin, fret-based controller, etc.  Generate MIDI note patterns or CC waveforms from digital or analog signals.  Re-purpose a “consumer” keyboard, calculator, game controller, or other electronic device as a MIDI controller.

These possibilities will be explored with “how-to” information at the blog and forums.

Have you registered yet?  The forums are the best place to ask for product information or technical support.

User Project Roundup, Part 8

exFade‘s modified Synsonics drum machine, MIDI-controlled via MSA-T MIDI decoder:

Bryan Benting’s MIDI-controlled electrical outlets and 48-output MIDI-to-gate box (with MSA-T-driven power relays and two MD24 kits for gate triggers) with MIDI-controlled lighting videos (video 1, video 2):

SYNCHRO‘s externally-housed MIDISpeak installations:

Concretedog‘s MSA-R mini review:

k1ds3ns4t10n‘s MSA-P assembly photos:

User Project Roundup, Part 7

Forum member GoatBoy used the MSA-R to provide MIDI control for an array of solenoid-activated bells.  (Note: The MSA-T and MSA-P may be better choices for solenoid-based projects.)

Spunky Toofers used an Akai EWI 3000 to trigger a MIDISpeak and effects.

Siempre La Luna documented the MIDISpeak assembly process and installation process.

Thomas S. photographed his MIDI Xbox controller for use with music games.

DIY 5x MIDI Thru / Repeater Circuit

Here is a MIDI standard-compliant 5 x MIDI Thru Circuit. Each MIDI Thru port generates an exact replica of the MIDI signal on the MIDI In port.

Parts List:

  • C1 – C3: 0.1uF Ceramic Chip Capacitor
  • C4: 47uF Electrolytic Capacitor
  • D1: 1N4148 Small Signal Diode
  • IC1: 7805 Voltage Regulator
  • IC2: 6N136 Opto-Isolator
  • IC3: 7414 or 7404 Hex Inverter
  • R1, R3-R12: 220Ω Resistor, 1/8-watt or 1/4-watt
  • R2: 10kΩ Resistor, 1/8-watt or 1/4-watt


User Project Roundup, Part 6

MIDI-modified Stylophone controlled with a bent TR-505 and MSA-R (Diabolical Devices):

Diabolical Devices MIDI Stylophone

MIDI2600-Internal installation video (Siempre La Luna):

DIY MIDI drum machine incorporating an MSA kit and a Farfisa organ percussion module (Quiet Channel):

MIDISpeak dual-mode installation (Erik Tinberg):

This Is The Sound, the new release from Burnkit2600 which features MSA-R controlled bent percussion:

Custom MSA-R based MIDI control box with video (The Umbrella Company):