## audacity-nyquist

 [Audacity-nyquist] generator with oscillation question From: Chris Capel - 2006-05-11 20:32:06 ```If I want to generate a sine wave that changes its pitch over time, such that I can specify time frequency pairs with interpolation, how would I do this? As an example, how would I generate a two second sine wave that starts at frequency 500, increases to 1000 by the second mark, and decreases back to 500 by the second mark? Ideally it would be some function (user-defined or not) that can be called like this: (make-my-sine 2.0 ;seconds 0.0 500 ;time Hz 0.5 1000 1.0 500) ;optionally more time Hz pairs I've played around with stuff a lot, but most of what I try ends up freezing audacity, I assume because the sounds I create are of infinite length and never stop evaluating when audacity tries to get the samples. Chris Capel --=20 "What is it like to be a bat? What is it like to bat a bee? What is it like to be a bee being batted? What is it like to be a batted bee?" -- The Mind's I (Hofstadter, Dennet) ```
 Re: [Audacity-nyquist] generator with oscillation question From: David R. Sky - 2006-05-12 07:17:22 ```Chris, Have you looked at fmosc? I've used it very little myself. Steven Jones wrote a plug-in quite a while back using it, it's on the Audacity Nyquist plug-ins page most likely, as well as on my site http://www.shellworld.net/~davidsky/seq1.ny I'm pretty sure I've seen documentation in the nyquist documentation on how to use fmosc. David (fmosc pitch modulation [table phase]) Returns a sound which is table oscillated at pitch plus modulation for the duration of the sound modulation. osc-table defaults to *table*, and phase is the starting phase (default 0.0 degrees) within osc-table. The modulation is expressed in hz, e.g. a sinusoid modulation signal with an amplitude of 1.0 (2.0 peak to peak), will cause a +/N 1.0 hz frequency deviation in sound. Negative frequencies are correctly handled. The sample rate is *sound-srate*. On Thu, 11 May 2006, Chris Capel wrote: > If I want to generate a sine wave that changes its pitch over time, > such that I can specify time frequency pairs with interpolation, how > would I do this? > > As an example, how would I generate a two second sine wave that starts > at frequency 500, increases to 1000 by the second mark, and decreases > back to 500 by the second mark? Ideally it would be some function > (user-defined or not) that can be called like this: > > (make-my-sine 2.0 ;seconds > 0.0 500 ;time Hz > 0.5 1000 > 1.0 500) ;optionally more time Hz pairs > > I've played around with stuff a lot, but most of what I try ends up > freezing audacity, I assume because the sounds I create are of > infinite length and never stop evaluating when audacity tries to get > the samples. > > Chris Capel > -- > "What is it like to be a bat? What is it like to bat a bee? What is it > like to be a bee being batted? What is it like to be a batted bee?" > -- The Mind's I (Hofstadter, Dennet) > > > ------------------------------------------------------- > Using Tomcat but need to do more? Need to support web services, security? > Get stuff done quickly with pre-integrated technology to make your job easier > Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo > http://sel.as-us.falkag.net/sel?cmd_______________________________________________ > Audacity-nyquist mailing list > Audacity-nyquist@... > https://lists.sourceforge.net/lists/listinfo/audacity-nyquist > > ```
 Re: [Audacity-nyquist] generator with oscillation question From: Chris Capel - 2006-05-12 15:57:54 ```On 5/12/06, David R. Sky wrote: > Chris, > > Have you looked at fmosc? Yup. As I said, the main problem I had was figuring out how to get things like fmosc, that don't have any end time and will keep returning samples as long as you keep asking for them, to stop generating so they could be returned back to Audacity. I tried things like EXTRACT and SET-LOGICAL-STOP and couldn't ever get my test plugin to not freeze up audacity. Chris Capel --=20 "What is it like to be a bat? What is it like to bat a bee? What is it like to be a bee being batted? What is it like to be a batted bee?" -- The Mind's I (Hofstadter, Dennet) ```
 Re: [Audacity-nyquist] generator with oscillation question From: David R. Sky - 2006-05-16 16:59:54 ```Not sure why this got re-posted, but the URL I gave is incorrect, it's http://www.shellworld.net/~davidsky/seq1.htm . David On Fri, 12 May 2006, David R. Sky wrote: > Chris, > > Have you looked at fmosc? I've used it very little myself. Steven > Jones wrote a plug-in quite a while back using it, it's on the > Audacity Nyquist plug-ins page most likely, as well as on my site > http://www.shellworld.net/~davidsky/seq1.ny ```