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Harmonic Xpander (Random Harmony Generator)

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Hi all,


I first became interested in random harmonic generation when I heard some early computer music while in college. I found it interesting and unique in that while it was unpredictable, when the programming was handled in the correct way, the resulting “music” - if randomly generated sound can be called that - had the potential to be mesmerizing. In 1987 Michael Brecker released his album “Michael Brecker” and one of the hallmark sounds on that disc was his use of the EWI (Electronic Wind Instrument) and synthesis to create an amazing palette of sounds. As an EWI player, I've been fascinated with his work. One of the most interesting things he did was to use a feature of the Oberheim Xpander module to randomly rotate through a series of harmonies. It works something like this:


The Xpander had a setting called “Rotate Mode” with 6 voice polyphony. Michael was able to turn that into an amazing harmonic tool by creating two zones on the synth, one with two “static” voices set to re-trigger and one with four rotating voices in rotate mode.





Voice 1 & 2 are static intervals set in semitones above or below the input note. Assuming a C3 is played, the static output would be C3 and G3 (seven semitones above C3 or +7). Every time C3 is pressed, the static voices will sound the parallel 5th C & G.


The rotating voices are set (relative to C3) to -10 (D2), -7 (F2), -8 (E2) and -2 (Bb2). Every time C3 is pressed the static 5th plays as well as one of the rotating voices in sequence. So:


Play middle C (C3) four times:

Voices 1 and 2 always play a parallel 5th C & G

Voices 3, 4, 5, and 6 play in rotation D, F, E, Bb Output would be [DCG], [FCG], [ECG], [bbCG]


The Harmonic Xpander functions in exactly the same way, but since it has been designed in Logic’s environment, it can be much more flexible and adaptable, and can be utilized in many different ways.


I created this in the environment and I've uploaded my "lite" version here for everyone's enjoyment. It's a fun and remarkably useful tool and can really kickstart your creativity bending your ear into really fun new places for composition and new harmonies. I've created a ready to play version with the Xpander interface in a floating window. Just open and go!





There is a pdf read me file included that covers the basic usage of the Xpander.



EWILabs Harmonic Xpander Lite V1.0.1 Files.zip

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