You used to be able to do surprising things with those old speakers using a timer interrupt: on an IBM XT it was possible to get 8kHz quality out of it, enough to make 4-channel MOD playback sound about as good as hearing it over a phone.
But your more typical use case was to play a single tone for some significant fraction of a second.
But your more typical use case was to play a single tone for some significant fraction of a second.