It is arguable whether speakers can suitably reproduce all the harmonics, but it'd still be more effective than beep beep beep beep beep beep.

[ //Could be a mechanical setup// [pocmloc]
Doh! of course. ]
-- FlyingToaster, Aug 04 2014

This would work brilliantly. I'd be awake to shut the alarm off 5 minutes before it went off every morning.
-- AusCan531, Aug 04 2014


Not the speakers you need to worry about, it's the high notes getting filtered out in the PA somewhere...tried this in a classroom, didn't work...damn.
-- not_morrison_rm, Aug 05 2014


Could be a mechanical setup, no need for speakers.
-- pocmloc, Aug 05 2014


Egads, analogue.
-- not_morrison_rm, Aug 05 2014


The mechanical thing should be quite workable. A chalkboard, originally, was basically a large piece of slate, a pretty common rock. And plenty of animals have claws/hooves made of the same stuff as human fingernails. So imagine such a claw being pressed against the slate, and begins to rotate on an axis when the alarm clock needs to make its sound....
-- Vernon, Aug 05 2014


Alarm clocks that waken you from sleep by making annoying noises is not really half-baked material. The idea needs a mechanical connection to a mechanism that creates the sound, as mentioned in [pocmloc's] annotation.
-- xenzag, Aug 05 2014


The claw (or hoof) would of course wear down with repeated applications to the slate [Vernon].

Thus producing a resale market for the stylus (should we call it?), an excellent elaboration on the idea, I foresee a great future for your company (can I buy shares?).
-- Skewed, Aug 05 2014


"Nailed it"
-- AusCan531, Aug 05 2014


for me it would be an incompetent child practicing the recorder. However the collateral damage on the nearby partner who doesn't have to get up is a worrying factor.
-- bs0u0155, Aug 05 2014


I'm not sure I like the notion of buying styluses (stylii?) for this. Why can't I use one of my own fingernail/toenail clippings for the stylus?
-- hippo, Aug 05 2014


Perhaps the user fixes their hand into the bedside clamp before falling asleep, the clamp holds their fingers so the nails are presented. At wake up time, the rotating disc of chalked slate is brought into contact with the clamped fingernails. The other hand has to be used to press the stop button.
-- pocmloc, Aug 05 2014


Alternate hands each night?

Then it has the beneficial side effect of keeping your nails filed.
-- Skewed, Aug 05 2014


A piece of damp expanded polystyrene foam, rubbed on a window pane ?
-- 8th of 7, Aug 07 2014



random, halfbakery