Wednesday, January 12, 2011

More on theory of creating canons in computer generated music

After posting on the concept of creating the same forms you find when scoring a canon but in computer generated music system. I revised a email on the subject. I thought it was a interesting view on the subject. So I thought I share it with the readers of the blog.

The response was sent by “Bohgosity BumaskiL

Changing quarter notes to eighth notes, and the rest of the notes in the
same proportion is the same as changing tempo. Similarly, scaling pitches up
or down (multiplying all pitches in hertz by the same frequency) will yield
an identical tune (in a different key). Augmentation is something you can do
to fifths and fourths without offending terminology purists. A perfect fifth
is 3:2. A classic augmented fifth is 25:16 (24:16 would be perfect). Your
use of "Diminution" is also about tempo. I am glad you are defining
inversion for me, because that is what I thot it means, and it provides
validation for a just intonation (tuning on the harmonic series) I promoted
in June (inverting it and scaling it by an octave work out to the same
thing, except on one key).

I've used fractint to get algorithmic music. Some of the best of what I've
heard comes from a "hopalong" fractal. It was called "the wizard".
Unfortunately, fractint works best under DOS, and I hav not even tested
whether winfract does sound. It does not handle skew, among other things.

One of my criticisms of fractint is that it adheres to 12TET, and I do not
know what to do about that. The alternative is perhaps as simple as scaling,
adding, and rounding. Perhaps I can add a third way for fractint to quantize
pitches. The first way is NO quantization, and I will hav you note that "The
Wizard" is quantized -- in a weird way, though: All of the quantizations are
powers of two.

1 comment:

  1. I've been working with creating canons by computer too, by using percentages (of both time and intervals) rather than ratios. It's not "just intonation" exactly, but...