On Sun, Jun 25, 2006 at 02:01:48 -0400, Dave Robillard wrote: > On Tue, 2006-06-20 at 08:35 +0100, Steve Harris wrote: > > On Tue, Jun 20, 2006 at 09:05:33 +1000, Loki Davison wrote: > > > Because people actually use them in Om, because people actually use Om > > > unlike certain other modulars. volt per octave is pretty damn obscure > > > in a computer program.... If i wanted to have a cutoff at concert A > > > what the hell is that in volts per octave?S > > > > Zero typically. I have to take issue with this, 1.0f per octave is the > > natural way to preresent things like filter cutoff in a modular. It's what > > makes the great modular systems so easy to work with. > > Nonsense. As a numerical unit it has no meaning whatsoever, and the > unit actually used has no bearing on the user interface provided (which > should of course be exponential).
It has a very specific meaning, +1.0 is +1.0 octaves. > The only sane unit for frequency is Hz. As Loki said, if I want a > cutoff at concert A, I (like any musician) know that's 440Hz. Whatever > arbitrary ugly real number it is in "V/Oct As Defined By AMS" is not > something I or anyone else cares to know. Any table of frequencies, or > math app, or damn near _anything_ that deals with frequencies will > present it in Hz. If you can come up with a real reason why this > arbitrary "AMS V/Oct" makes any sense in a _digital_ modular, I'd like > to hear it. It's all about modulation, if I connect a [-1.0, 1.0] sine LFO to a cutoff modulation input then I want it to modulate up and down by N octaves, not N Hz, frequency-linearly symmetric modulations sound wrong. My favourite (digital) modular filters have a centre frequnecy (shown in Hz, expoentialy scaled control) and a modulation input that modulates in octaves. You want the modulation to be musically relevent, and the most musically useful unit for pitch is octaves :) Humans aren't SI sadly. I agree that describing it as volts is a bit odd, but it instantly makes people like me feel at home. There's not reason why a digital modular neds units for its modulation sources. It's just real numbers. - Steve
