Part two: breadboard 555 mini-synth

This was the first draft of my synth, I followed a post by lonesoulsurfer: https://www.instructables.com/Moog-Style-Synth/

I decided to construct the VCOs with 555 timers instead of the LM358s that he used here (couldn't get the oscillator circuit to work with the button circuit).

This is my VERY rough first draft of the keyboard circuit:

As you can see, it's all connected, so you'd only be able to play one note at a time. This is not ideal , but I was happy to get the first part working!

Here's a picture of the breadboard circuit:

This is two 555 timers: one creating the different notes via the button circuit, and one as a modulation circuit hooked up via the trim pot. The third chip is an op amp that is connected to the 8-ohm speaker I was using for testing.