Simple Arduino Synthesizer Build

How I put together my Arduino synth. It's a very simple breadboard electronics project. I've put a link with the code below. To make this work you'll need the HC-SR04 file added to your library, the file is also linked below, and finally is a link where you can download the Elegoo Super Starter Kit which has a whole load of file that can be added to your libraries and some good info on how to install stuff along with a bunch of nice lessons, click the link then select UNO R3 Starter Kits, then Elegoo UNO R3 Super Starter Kit.