City Street Drone: is a bank of square wave oscillators with one audio out and mute switches for each channel. Each voice uses a modified S9018 Bipolar Transistor to create a pitch-adjustable square wave.

I designed this board to achieve a sound somewhere between a 3 voice chord, an orchestrated swarm and just droning noise (video demo coming soon).

Each voice has an LED that modulates in time with the oscillator. The mute switches for each voice allow the user to use as many of the voices as needed. An 1/8" jack provides cv modulation from external gear. The cv jack is isolated by the homemade vactrol so gear that runs on other voltage should work.

The vactrols used on this board are made from a photoresistor connected to an led with heatshrink tubing. For information on how to make a vactrol by hand check out this video

**NOTE ON CAPACITORS: Each channel has a suggested capacitor value but these can be adjusted and played with for different sounds. A higher value will give a lower range of sound (i.e. a 10uf capacitor will give a much higher pitch than a 100uf capacitor).

Runs on a 9volt battery or external 9volt DC power supply.

Buying Options: Just Board: components will have to be sourced by buyer. Partially assembled: Comes with homemade vactrols, Potentiometers transistors and Audio Jack. DOES NOT include resistors, leds, and capacitors Fully assembled: all components included and soldered to board

Board comes 89mm*47mm.