Gothic Choir is a Midi Audio-Visualisation Tool integrated with Unreal Engine 4.

Video - https://youtu.be/4Jtyb2D03W8

Use your Midi Device like Midi Keyboard or Synth with Midi Connection to play with Gothic Choir or you can play using your mouse or pc keyboard (Shortcuts applied to E-P keys).

For playing with MIDI you need to have Midi Device (Midi Keyboard or Midi Pad and etc.) Especially this product works fine with Midi Keyboards or Hardware Synthesizers with MIDI and the principle is a simple Sound Font Instrument or Virtual Instrument (VSTi) but in Unreal Engine 4 Virtual Space.

For use in other projects make sure the required plugin is enabled:

Plugins > Input Devices > MIDI Device Support