[PD] math + music examples

Mathieu Bouchard matju at artengine.ca
Thu Mar 24 16:13:19 CET 2011

On Thu, 24 Mar 2011, Joe wrote:

> good one, Mathieu
> why is it that on this chart http://www.phys.unsw.edu.au/jw/notes.html
> 55 is G3, not G4?

Because I'm too lazy to do the [- 1] and I don't rely on my octave numbers 
being in sync with anyone else's.

MIDI's note number 0 is C in octave -1. It's not audible. MIDI has 10⅔ 
octaves, simply because for binary coding reasons they had 2*2*2*2*2*2*2 
possibilities. There were already plenty of annoyingly-high notes in 
there, so they thought that they'd rather complement it with an unhearable 
octave. (!)

But Pd has no such restrictions and can use all sorts of impossible MIDI 
notes and lots of microtonal resolution between them... as long as you 
don't try to convert to real MIDI codes. Note number -120 is the C of 
octave -11, note number 666 is the F# of octave 54. Note number 69.0001 is 
one 1% of 1 cent above A4.

In _this_ mail I did subtract 1, to comply with the chart.

| Mathieu Bouchard ---- tél: +1.514.383.3801 ---- Villeray, Montréal, QC

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