OVERVIEW

So what the heck is a MIDI Goblin made of anyway?

In short: its a relatively simple esp32 device.

The heart of the MIDI Goblin is a ESP32 WROOM 32D DOIT DevKit V1 - they’re cheap, abundant and quite powerful. Think arduino, on steroids. More program memory, more RAM, a better CPU - they even have bluetooh and wifi built in - but to keep things simple and keep as much program memory free as possible, MIDI Goblin does not use the wifi or bluetooth connectivity.

credit: instructables

Many PCB manufacturers actually allow you to implement esp32 in your own pcb designs. You can also buy surface mount versions as well if you’re handy with a soldering iron (or heatgun)

MIDI Goblin takes a slightly different approach and is more like a hat for the esp32. It might even seem like a dumb approach - but hear me out - off the shelf components are typically quite reliable, safe, cheap and in the future, if there’s an esp32 that conforms to the same footprint - potentially upgradeable.

Plus if you for some reason just find MIDI Goblin totally useless, you can yoink the esp32 out of the case and use it in one of your own projects….it doesn’t need to become e-waste.


(just pry the front of the plastic enclosure away from the esp32 about a millimeter and gently remove the esp32 from the headers)

Other than the esp32, what else is a MIDI Goblin made of?

  • A micro sd card reader (also off the shelf)

  • Two 5 pin MIDI DIN connectors

  • An enclosure made by Polycase

  • An encoder(with built in push button

  • A 1.3” SPI white oled screen.

  • A 16 channel multiplexer (used to read buttons)

  • 15 pushbuttons (16 if you count the encoder button)

  • A custom PCB to connect everything to the esp32

Interested in seeing how everything is connected? Check out the schematics page. Although I wont be uploading the PCB gerber(for the time being at least) - If you can read a schematic, and are good with breadboarding or pcb design, there’s nothing stopping you from creating your own custom MIDI Goblin - feel free to download the arduino sketch (warning: it might take a while for anyone new to this kind of thing)