I’m asking not specifically about smoke detectors but any device that beeps but does not make any other, non-beeping sounds. Examples include microwaves, the timers on ovens, the fare system on a bus when you give it your fare, the little beepy heart monitor things in hospitals and old-school digital watches. These things beep but they seem to only beep; they do not make any other, non-beeping sounds.
So my question is: how do these things beep? It must be a speaker right (?), and if it is a speaker then why do these devices never make any other sounds other than beeping? (Because presumably speakers have a greater range than just a few beeps.) Or do these devices have specialized speakers that can only make a few sounds? If so, how do these speakers work?
I’m not sure if I articulated this very well but hopefully that makes sense.
Depending on how briefly they can be triggered i wonder if it could be fired in a controlled enough temporal pattern to create recognizable notes. Human hearing goes down to 40 cycles per second, so if it can fire in burst of less than a 40th of a second then that could work
The link I included in my comment goes over driving one in recognizeable notes to play the nokia tune. It’s worth a read if this concept interests you.