Here is an interesting idea for speakers that could change everything.

Instead of using a vibrating a driver at the correct frequencies and projecting them, this one uses ultrasonic waves to vibrate air molecules along a path, so things outside the path won’t hear the sound.

In other words, you send the sound directly to your ears without the use of any sort of headphones. Of course, you have to be sitting in a very specific sweet spot to see it.

However, if I was sitting at my desk, I know only of the stable spots at my ears where the sound would be sent.

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