My collaborator Malek Lopez and I were playing around with some MIDI sequencer code. Based on his desire to have a rhythm generator, I kludged a 16-step sequencer that would spit out a sequence of 16 commands. For the sake of simplicity, let's say the sequencer did this by randomly choosing a number between 0 and 2 sixteen times, and putting its choices into a list.
So for instance, it might spit out: 0112 1020 2201 2021
The number sequence was then read as a sequence of tags/commands according to the following system:
0= start a note; 1 = end a note; and 2 = do
Now, if we assume that the numbers determine the gating of a single sustained pitch, then the sequencer would output a sound that could be represented as:
Where a stretch of blue squares indicated a sustained pitch, and a stretch of white squares indicated silence.
After listening to the sequencer do its thing for a few hours. I realized that changing the way the sequencer interpreted the commands would create musical phrases that would differ from one another, and yet be related by rules of translation.
The most obvious variation would be produced simply by inverting the interpretation of the start and stop tags, ie
0 = stop note; 1 = start note; 2 = do nothing.
Well, I said it was the obvious variation. It produces a negative of the previous sound, where previous tones are replaced with silences of equal length, and previous silences are replaced with tone.
However, if we use a different system of tag interpretation, say
0 = do nothing; 1 = start note; 2 = end note;
then we get something like this:
Which is a sonic product with a different and less obvious relationship.
I'm currently referring this kind of variation as Translection, as it consists of changing/shifting the way the tags are read ("lector" = reader, from the Latin verb legere: "to read"). I find the idea of translective variation interesting because this kind of variation is native to music made with computer code. As far as I know, it is not a named, known or acknowledged form of musical variation. Still not sure where it goes from here, but tag-shifting functions will definitely be coded into the coming sequencers we'll be making..