Jetée

I don't think the human ear works like a radio transmitter.
There's no variable-valve tuning we can do, nor pitch elevation increase/decrease; all we can really control is the occasional maintenance and gunk clean-up.
While it is a fascinating process in learning exactly how the human ear works, it's by no means the animal kingdom's most refined example, and our own range in audible discernability is quite miniscule in comparison to other common comparables (a dog, a cat, the goldfish, a pigeon, a snake, etc.).
There are limits and outer-limits to which sound, frequency of, & decibel rating we can tune into, and which have abslutely no effect on us,
(meaning we can never hear, or even perceive a noise is being produced, despite that there is one, and other animals can detect it, while we, sadly, remain oblivious to it) or other higher scalings, which may exert the potential to seriously harm, if not fatally injure, us, depending on the root cause, and sheer force to what it is we are hearing (like a shooting gallery taking place in your kitchen).


On the short side of the scale to your hypothetical point of inquiry: I say, no, you cannot hear the digital wristwatch alarm beeping from across the room, if given there is a gathering cloister of people in the room, they are socially well-adjusted (re: talking) and there may be an ambiance filter in the room as well (the televised golf tournament, or some Dance Party Mix CD '96 playing in the background).

Perhaps if in the hypothetical everyone was silent, not moving, and/or sitting down and stationery, you could hear the beeping. But, if you were to remove the variables, and also to assume that there were a fair and common number of persons (as defined by the type of shindig you were attending) and space in-between (say, 10 people and about 20-25 feet away, at minimum) you and the friend with his ill-timed calculator-watch alarm, there could still be a chance your anticipatorily-awaiting ears will not be perceptive enough to notice anything, due to the interference, (soundwaves would bounce and disperse off the bodies, getting easily jumbled) and also due to the distance in relation.

There's also no real accounting for how crappy your buddies beeping watch really is. What, did he find it at the bottom of his cereal box? How do you even know how loud his watch alarm can really be, if it only has the one setting, (most do) and is fixed just so loud, and for a defined period of time (maybe 1-3 min., on average) that it reaches the one wearing the watch, in his/her immediate vicinity, and outwardly spreads the beeping only so far that it does not become a nuisance to others. All of these factors weigh into your imagined scenario, and while it might be a tad bit diverting to think of all the variables, I say you just opt for a few field tests to see what you, yourself come up with, and report back.


What do you say?

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As human beings, our greatness lies not so much in being able to remake the world (that is the myth of the Atomic Age) as in being able to remake ourselves.

—Mohandas K. Gandhi