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Re: Generators

From: Jussi Kalliokoski <jussi.kalliokoski@gmail.com>
Date: Tue, 13 Mar 2012 22:23:48 +0200
Message-ID: <CAJhzemUANGDx8fyRP=4=wWyDOPHO1Te5a+BKZae6kdpf2Dx2ag@mail.gmail.com>
To: philburk@mobileer.com
Cc: public-audio@w3.org
On Tue, Mar 13, 2012 at 9:06 PM, Phil Burk <philburk@mobileer.com> wrote:

> Hello Chris,
>
>
> > has any one seen a simple example of generating a sine
> > wave that can be swept using a slider,
>
> This web page has an example of a sine wave oscillator.
>
> < http://www.softsynth.com/**webaudio/tone.php<http://www.softsynth.com/webaudio/tone.php>
> >
>
> It maintains a phase variable that is incremented for each sample. The
> frequency can be swept or modulated without glitching by updating the
> phaseIncrement variable.
>
>
> > for example, up to high
> > frequencies without aliasing?
>
> You don't have to worry about aliasing when using a sine wave unless you
> are modulating it at audio rates. Aliasing is a big problem with sawtooth
> and square waves because they contain high frequency partials that go above
> the Nyquist rate.
>

>From synthesis point of view, aliasing isn't always even a bad thing, it
has a lot of useful applications like filter exciting and such, used to a
memorable effect by such classic synthesizers as Roland JP-8000 (Supersaw,
anyone? :P).


>
> Phil Burk
>
>
Received on Tuesday, 13 March 2012 20:24:20 GMT

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