The Chaos Engine is a 5 oscillator mini synth. Despite it's lo-fi discrete transistor design and very simple panel layout, it can produce a huge variety of sound textures. These range from simple bleepy melodies reminiscent of The Silver Apples, to fractal noise and spluttering sonic convulsions similar to the sound of fax machines or old computer tapes. Because of it's fractal-like qualities, the slightest microscopic knob turn can totally change the sound.
The Chaos Engine has 3 basic modes of operation
The oscillators do not influence each
other. In this mode it is like a primitive keyboard,only
with the added creative possibilities of being able to tune
the notes individually.
The oscillators are all synchronized to
oscillator 1. As you turn the tuning knobs the pitch
will not glide as normal; instead you will hear a
series of harmonics, sometimes very musical and strange
The oscillators all try to sync to each
other. This is controlled by the chaos depth knob and produces
the widest variety of sounds.
The circuit is discrete transistor because I believe it produces the richest possible analogue sound, and because many of the timeless legendary effects and synthesizers are discrete transistor, e.g Minimoog, Univibe, Big Muff, Cry baby/Vox Wah. There is an intangible quality to their sound which is not present in modern Op-Amp equivalents.
Maybe I'm crazy for spending so much time constructing these cases, when I could have opted for the typical pressed steel jobby, but I think they look pretty cool, in a kind of retro industrial way.
It is availble in SchneidersBuero
The polarity is center negative for the power supply connection. The circuit is protected if you get it wrong, so don't
be afraid to try it if the polarity of your supply is unclear. I have chosen the most common type of power socket,
Some power supply tips have a hole down the center that
is too big even though they appear to fit correctly, this is worth checking of you don't get any sound.
The keys are not latching so the only sound when they are pressed.
The chaos depth knob only really creates a strong effect when it is turned nearly all the way up.
In this mode it is like a primitive 5 note keyboard. It would be fun to play it through a real tape delay in this mode.
Harmonic sync undertones
Oscillators 2 3 4 5 lock on to harmonically related notes of oscillator 1. The notes form a type of minor scale. Try tuning the notes to a nice chord and then turn knob 1 this makes a really strange detuning sound.
All oscillators try to lock on to each other. In this mode oscillator 1 can bleed when it is not being played, so it can be switched off by turning it's knob all the way up.