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Comment by a9h74j | Hacker News Reader

This and the posted article mention a speaker or driver. No mention of how they deal with aging or fatique effects in e.g. a flexible ring connecting to the frame and holding the cone. Have done applications where a special "high cycles" acoustic driver had to be sourced.

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i hadn't thought about that; it seems especially important given that they're talking about kilowatt power levels and macroscopic wavelengths, so a nice piezo probably won't cut it

how did you source the high cycles driver, what was it made of, and how much did it cost

I just found this[1] which mentions rubber vs. foam surrounds (suspensions), and butyl rubber with apparent good life. (That might have been the simple difference; the normal-looking speaker was already sourced; I came in to do embedded/DSP.) At kilowatt/constant power levels I'd imagine going as far as oil/magnetic suspension for high life; even o-rings under high cycles can fall apart.

I'm pondering how one would do accelerated reliability/life testing for the acoustic heat pump application. Maybe they have good-enough FEA/multiphysics on a suspension and cone, and strain/life curves they are prepared to trust. With a slope on log-log strain vs life they might project how much to overpower/overstrain for an e.g. 1000hr accelerated test.

[1] https://www.avforums.com/threads/speaker-life-expectancy.164...

thank you very much

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