Re: [LAD] [LAU] from 4 to 400 Hz

> On 07/17/2011 10:41 AM, Rustom Mody wrote: >> On Sun, Jul 17, 2011 at 1:21 PM, Philipp Überbacher >> <hollunder(a)lavabit.com>wrote;wrote: >> >>> Excerpts from Rustom Mody's message of 2011-07-17 05:33:44 +0200: >>>> I am preparing to give a talk on the wider ramifications of music. >>>> One of the things I wish to demonstrate is that things that look >>> different >>>> are merely analogs but at different scales. >>>> >>>> eg if something vibrates at 400Hz we hear a sound of A-flat. If it >>>> 'vibrates' at 4 Hz we hear a beat. >>>> In the same analogy a 2 vs 3 poly-rhythm (should?) change to a >>>> do-so >>> chord. >>>> And so on. >>> >>> I suggest you do some experiments before you give a talk. At 4 Hz >>> you >>> won't be able to hear anything, you won't even be able to reproduce >>> a >>> 4 Hz sound with common speakers. >>> >> >> You took me quite literally, [I did put the vibrate into quotes :-) >> ] >> Let me spell out the experiment in more detail: >> Say I have a rhythm in 4/4 time -- 4 even quarter notes, bar >> repeating >> every >> second played by say a click. [What kind of click I am not very >> sure; >> sharp >> with few harmonics would be best I expect] > > Exactly. Just take a short audio-sample (aka grain) and trigger it > repeatedly. Increase the trigger freq. (aka grain-speed) from 4 Hz -> > 400Hz. > > Search the net for granular-synthesis. Your use-case is not the > typical > grain-synth application, but the principle is the same. > >> Now if there were some (realtime) way of sliding the tempo from 1 >> sec >> to >> millisec I expect the separate clicks would vanish into a hum at >> some >> stage. >> >> This (and other such experiments) is what I want to demo. >> Ive started looking at chuck. >> How does it compare with puredata? >> > > It's a bit of an apples vs oranges question. > > the main difference: Chuck you program in text, pure-data you > graphically connect "objects" (if you know Max/MSP: pure-data is > similar). > > AFAIK, Chuck does not offer GUI elements - you'll need to implement > the > slider via OSC or use a "text slider". > >>>> Is there some kind of software where I can make a 4 Hz beat and >>>> pull >>>> a >>>> slider or a freq text box entry until it sound like a A-flat note? >>> >>> puredata springs to mind, it's easy to use and has everything you >>> need. > > Indeed. Though chuck, supercollider, csound,... could all do the > trick. > > If you know neither of those. Pure-data is probably the easiest to > get > started with. > > http://www.timvets.net/video/grains.php will do what you want with > Pd. > I'm not sure that does what he wants. He asked for a tool that takes an existing signal/tone and then down tunes it. What you are suggesting creates an emulation of that process but generates a completely new signal/tone. It would achieve a similar sound but is functionally quite a different process.