Mini Grant Winner : MIDI Guitar

This blog was written by Julian Tang – the winner of the MakerSpace Mini-Grant for the month of November, 2018.

MIDI Guitar

This project is a MIDI guitar that utilizes sensors to capture the action of the player’s actions, and sending this data to computer-based audio synthesizers in real-time. It enables guitar players to tap into the endless possibilities of digital audio synthesis; electronic musicians can also use it to gain natural and intimate control of sounds. MIDI(Musical Instrument Digital Interface) controllers of various forms have been around for a long time, although MIDI guitars have been largely absent. In recent years, various companies have been attempting to create such devices. However, conformity to market trends have led most of these products to be scaled-down versions. Some are branded as guitar learning tools, and some of them are designed to interface with iphones which lack the processing power for ideal audio reproduction. This project aims to create a full-sized, high performance MIDI guitar that uses unconventional electronic and digital processing techniques in order to surpass the theoretical limits of low-latency signal interpretation.

I applied for the mini grant at about when I just managed to make it talk to my computer via USB

Rough drafting for additional subsystems. five potentiometers were planned for ergonomic placement.

The support structures, touch caps and the circuit board are designed in Autodesk Fusion 360, and 3D printed at the same time using the Stratasys Dimension Elite. The circuit board is designed in Autodesk EAGLE and built using Othermill machines.

In the beginning, everything electronics were sitting on a breadboard. It was not a good idea even in the early days of the prototyping process, as this device experiences a lot of vibration. In December, a sufficiently satisfying circuit design was completed, and it was time to move on to a circuit board. The boards were designed in Autodesk EAGLE. Othermill machines are used to create them.

Additional sensors are being added at this time: piezo discs that function as simple drum triggers.

Drafting for neck-bolted potentiometers and buttons!

Soon later, the support structure and the pcb were made.

Working on it takes lots of space!

Modular design pays off here. Installing the battery cases and the ON/OFF switch was made easy and quick, because it only required me to take measurements of their dimensions and create 3D printed parts that fit them. No cutting/drilling was required, and I only had to unscrew a couple of bolts to replace the old, flat side panels. More batteries go on this device compared to acoustic-electric guitars because the onboard signal processors need to be powered separately.

Laser cutting for backup top panels due for spray painting. Modular design ensures that they can be swapped within a minute.

Current progress. Electronics are functional and the painted panels look good.

This project will continue to be optimized and polished. On a lucky day you’ll see it there, so see you in makerspace!