i’m generally obsessed about time on stage and have used many versions of clocks over the years.
i just recently commissioned a giant double pendulum to take care of some rhythmical duties to the structure of my performance while i do some programming on stage:
likewise, i’ve been using a mic’d euler’s disk to take care of some clock duties recently, though it only lasts for a couple of minutes:
there’s another amazing double pendulum which i can’t really find for sale anywhere that’s realistically affordable:
and something i used for years when i was starting out was a standard alarm clock, just the regular analogue kind with the 2 bells on top which you can wind up. it was great to have 20 of these all set to go off at the same time- set them for, say, 1 hour to create the end of the show. of course they were not very well made so they would all go off at slightly different times and it was a really fun game and good way to get interrupted and know when to stop!