“This is my 3rd Fizzle Loop Synth circuit and it builds on the previous 2 which can be found here and here.
The heart of the synth is 3, 555 Timer IC’s which are used to make some really interesting beeps and boops. The difference between this version and the others is; I have reduced the number of IC’s down to 3 (version 2 have 4!), the rhythms and sounds you can make from this version are in my opinion are better and lastly, there is a drum sound option which gives some really cool beats.
I also have shrunk this synth into a pocket sized one. By placing some of the capacitors directly onto switches and shrinking the prototype board down, I managed to stuff all of the pots, switches and components into a small flashlight case.
You could probably use something like an altoids tin as a substitute case.
I have also been playing around with designing schematics and have included a circuit diagram which (I hope!) is easy to understand. I’ve also decided not to do a step by step guide to making the circuit as I don’t really think it helps too much. However, if I’m wrong let me know and I’ll do it in the future. What I have done instead is described some of the trickier sections and have added explanations where necessary. Such as what a Vactrol is and how to make one.
Finally - I’ve made a video of the synth in action so check that out to hear how it sounds.”