The theory goes like this: all a speaker is really doing is pushing air around, and if you can get it to push enough air, with enough force, you might be able to push droplets of liquid out from where they came. “The lowest tone that that speaker can reproduce, at the loudest level that it can play,” says Eric Freeman, a senior director of research at Bose. “That will create the most air motion, which will push on the water that’s trapped inside the phone.” Generally, the bigger the speaker, the louder and lower it can go. Phone speakers tend to be tiny. “So those YouTube videos,” Freeman says, “it’s not, like, really deep bass. But it’s in the low range of where a phone is able to make sound.”
The best real-world example of how this can work is probably the Apple Watch, which has a dedicated feature for ejecting water after you’ve gotten it wet. When I first reached out to iFixit to ask about my water-expulsion mystery, Carsten Frauenheim, a repairability engineer at the company, said the Watch works on the same theory as the videos. “It’s just a specific oscillating tone that pushes the water out of the speaker grilles,” he said. “Not sure how effective the third-party versions are for phones since they’re probably not ideally tuned? We could test.”
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