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Showing posts from February, 2022

Eurorack Level Display

This build was inspired by this post from ElectroDruid , at least in part. I have been getting into sound synthesis over the past year and needed simple module on my Eurorack setup that I can plug anything into and see if it's working (or peaking). There are a few modules out there like what I've made here but I'm doing most of my synth as DIY kits or pure DIY of my own design. The idea started on the breadboard, and because I had an Arduino Pro Mini in my box of spares that's what I used.  Here all 16 outer pins of the Pro Mini and two of the inner analog pins are connected to the row of LEDs each of which has a series resistor. for a total of 18 LEDs, which was later reduced to 16.  There were still two analog pins available (the green and yellow wires) which were used as audio inputs. The other two analog inputs were later used for some timing/debugging. The audio and control signals on Eurorack can swing ±10V which would damage the Arduino if used directly. To solve