Peter O'Doherty wrote:
Hi list,Apologies for the dumb question but could someone explain why these two expressions result in a different sound?
Linear ("additive") changes in MIDI pitch (note numbers) result in exponential ("multiplicative") changes in frequency (Hz). Adding 12 to a note multiplies the frequency by 2.
If you have a straight line in (note, time) and do .midicps on all the points, you get a curve in (freq, time), but if you do .midicps on just the end points first, you get a straight line in (freq, time).
If you're an algebraist, (note, +) is isomorphic to (freq, *): http://en.wikipedia.org/wiki/Isomorphism#An_operation-preserving_isomorphism
{Saw.ar(Line.kr(24, 108, 10).midicps, 0.2)}.play;{Saw.ar(Line.kr(32.703195662575, 4186.0090448096, 14.56761754744), 0.2)}.play;Whereas these are identical: {Saw.ar(24.midicps, 0.2)}.play; {Saw.ar(32.703195662575, 0.2)}.play;I guess it's got something to do with converting the dur value of Line.kr but I can't figure out what; if you do this{Saw.ar(Line.kr(32.703195662575, 4186.0090448096, 10), 0.2)}.play; it's still not the same. Thanks, Peter http://www.peterodoherty.net
Thanks, Claude -- http://claudiusmaximus.goto10.org