Hi C688...

I already knew that and have already done similar in some Linux flavours but there is no such animal as /dev/dsp in Apple gear. There is not likely to be either so __direct__ access to a device is not possible. Hence the use of OSX's afplay command that exists in virgin OSX installs.

Bazza...

EDIT:
You might be interested in this I wrote a few years ago:-
Metronome For Beginner Musicians... « Python recipes « ActiveState Code