Re: changing a sound signal while listening to it

[Dan Stowell <dan.stowell@xxxxxxxxxxxxxxx>]

In SuperCollider this code does a simple version of what you describe:

(
s.waitForBoot{	
  {
    var centre = 440;
    var beat = Integrator.kr(KeyState.kr(124) - KeyState.kr(123))
           * 0.01 + 10;
    var amp = Integrator.kr(KeyState.kr(126) - KeyState.kr(125))
           .linexp(-5000, 5000, 0.001, 1);
    (beat*2).poll(1, "beat freq");
    SinOsc.ar([centre+beat, centre-beat], 0, amp).sum.dup;
  }.play
}
)

arrow keys up/down for volume, left/right for beat freq.

Dan


On 10/08/2010 03:32, Daniel Bowling wrote:
> Dear List,
>
> I am trying to create a piece of software that will allow a subject to
> change the beat frequency and amplitude of a signal while listening to
> it in real time.
>
> More specifically, the signal will consist of two pure tones (e.g. T1 +
> T2), and the difference between them (T2 - T1) as well as the root mean
> square amplitude will be under the control of the subject via the keyboard.
>
> I have tried to execute this in Matlab using a loop, the problem is that
> the sound stops and then starts again at the beginning of each loop
> iteration.
>
> Can anyone suggest a way this might be implemented on a computer? Or
> perhaps just a suitable programming language?
>
> Thanks,
>
> Dan Bowling


--
Dan Stowell
Centre for Digital Music
Queen Mary, University of London
Mile End Road, London E1 4NS
http://www.elec.qmul.ac.uk/digitalmusic/people/dans.htm
http://www.mcld.co.uk/