Binaural Beats w/ Squeak

I'm still rather new to Squeak, so I decided to start working on a
small sound project.

I want to produce Binaural Beats, which ultimately means that I need
to be able to produce sounds at a certain frequency for a given length
of time.  it's more complicated than that, but I'm trying to find just
this starting point.

Can anyone offer some kind instructions for playing a specific tone
through my system's audio card?

Thank you,

Michael