Mroztronium 1


                                      Prototype built 1/30/17

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https://soundcloud.com/mroztronium/1a-1

This instrument is greatly indebted to the work and ideas of Rob Hordijk and Doc Mabuse (theaartworks.org). I've built many different versions of Rob's "Rungler" into instruments and was curious to try designing a Rungler-based instrument that used amplitude modulation along with some other tricks. This instrument can work as a standalone device to produce a wide variety of chaotic behavior. The extra outputs make it equally capable of controlling other voltage-controlled instruments.

The VCOs are akin to early Buchla VCOs in that they are useless for precisely playing musical scales with a conventional 1V/octave keyboard, but exceptional for FM experimentation.
They have a roughly exponential CV response.
The sync selector switch on VCO2 does many interesting things when the VCOs are cross-modulated via each other and/or the DAC.
The auxiliary CV inputs are high impedance and ripe for use as "body contacts". Just plug in a cable or bare banana jack stud and poke away.

There are two waveform outputs available from the DAC.
The Stepped output gives chaotic stepped waveforms, useful as audio or a control voltage.
The Smooth output has variable lag time and is best used as a control voltage that gives a
slewed version of the Stepped output.
The Recycle switch allows you to select whether the DAC is sampling or storing. This is useful for storing random digital wavetables.

The DAC + XOR + Clock Divider chain gives a complex series of pulses for triggering the Envelope Generator, which in turn controls both output VCAs simultaneously.
The envelope generator also has its own dedicated CV output.
The AM outputs give a stereo image derived from the VCO sawtooth waves mixed with stepped waveforms from the DAC's shift register.
The VCAs are vactrol-based and create a nice plucking effect with short decay times.

A steady droning signal is available at the XOR output.
It sounds sort of like a ring modulator.

Edition of 1