Testing the different parts for the synth on Breadboard

A project log for 8 note Step Sequencer

This is a synth that produces squarewaves in different frequencies. You can use it to make a pattern of maximum 8 notes.

Mathias SundgrenMathias Sundgren 03/17/2016 at 11:170 Comments

Breadboard test

I started experimenting on the breadboard. I tried different capacitors for the 555-timers and picked the ones that suited my project. When I was testing the synth I didn't use all the potentiometers, LED's and transistors. I only used 2 potentiometers, 2 LED's and 4 NPN transistors because I didn't have enough space so I could only hear two notes, witch makes it harder to choose the right capacitors for the IC's. Why? Well, because I can't tell how fast the loop will run at when I connect all the components so I can hear all the notes one after the other. The combination of the potentiometer and the capacitor affects the speed of the loop. I hope you understand, if not ask a question in the comments!

After I made the Synthezeiser I made th schematic.

I came to the conclusion that a small capacitor should be used for the sound-producing 555-timer and that a bigger electrolytic capacitor is better for the speed controlling 555-timer

Here is the full breadboard test online ( with 8 notes: