Audemars Piguet Royal Oak Concept Acoustic Research
Now we're fully into geek-out territory. Minute repeaters are these tiny mechanical functions that are tacked onto insanely complicated watches. They were designed for use after dark, when, let's say while you were traveling in your horse and buggy, you wanted to know the time. Nowadays we have electronic notifications, we have super luminova paint that glows in the dark, and heck, Timex's have had indiglo for like 40 years. But this function allowed you to hear the time, much like Big Ben in London. They actually have tiny acoustic hammers that hit acoustically tuned metals inside the watch, clanging out the time in hours and minutes.
Until now, though, these have been remarkably quiet instruments, audible to only the wearer, and usually only if he was in a quiet room. What AP has done here is create what is now considered to be the loudest minute repeater mechanical watch in existence. I had the pleasure of hearing it, and it's suspiciously loud. Like hear-from-across-the-room, loud.