changing a sound signal while listening to it

[Daniel Bowling <danielliubowling@xxxxxxxxx>]

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