Lunetta Synth

My first attempt of building a “lunetta” synth based on CMOS logic chips. I used one 40106 Hex Inverting Schmitt Trigger. Yeahh!


Raw lunetta recording

For the geeks:

This chip contains 6 individual Schmitt triggers. A Schmitt trigger is a comparator circuit that incorporates positive feedback. What this means is that when a high signal is applied to the input pin, the output pin generates a low signal. This simple circuit can be connected to a resistor/capacitor pair to rapidly turn on an off. When the frequency of this on/off conversion is in the audible range, we hear a square-wave tone.


I created two oscillators modifing each other. This is as low as it can get – no envelopes etc. The push button is triggering the signal, the switch is used to change the waveform from square to sawtooth – which isn’t working really well. The two knobs are changing the speed of the oscillators. The motivation for building this is more about the process then the actual sound. It sounds horrible but it is nice to build something out of cheap supplies that creates different sounds everytime.

Lunetta recorded through different guitar effect pedals

Lunetta and Moogerfooger midiMurf

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