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Monthly Archives: December 2008


DRONE sounds SYNTH, cased inside an old router box. Chaotic but under control.


The circuit for this instrument is quite simple, four 555 in astable configuration gating and four oscillators made with just one 4093.


click to enlarge

The interface is arranged as four channels across,each one has three switches and two potentiometers, and LED showing it’s state:


So for each channel, the first pot (50k) controls the freq of pulse coming out from the pin3 of each 555; this signal can be routed to main out (resulting on a pulse beating oscillation) or to gate each of the 4 oscillators made with the nand gates of the 4093. the second pot (1M) controls the pitch of the gated oscillators on IC 4093. the switches allow for some tweaking on each channel, either pulse ore gated/osc mode,also the indispensable channel on/off, and finally the third switch connects the pins 5 of the 555 (voltage control?) to the main out resulting on some interesting broken rhythmic patterns…for some magic of electronic randomness…All switches positions can be use combined into several different modes,and like always (I’m not an engineer) the oscillators affect and modulate each other..sometimes beautiful harmonies occur inside the rhythmic pattern…drone2



The result is an instrument that is fun to play, because while it has it’s random magic sound remains totally controllable.

Here is a video of the DRONE in action performed by 9volts & ChairB and recorded by LucySombra.

video of PyR 2009 | PyRformance Alba G. Corral + Nikka

Nikka is owner and user of Drone Synth