Quote Originally Posted by Smokey
I don't know if that day will ever come. The way our ears are designed (ear drum), a device is always needed to create sound [pressure] waves.
I guess it depends upon your definition of a "device". There have been a few successful ion plasma tweeters produced over the years that are massless. The Hill Plasmatronics speaker had a wonderful tweeter. The Acapella tweeter is in current production. The trick has always been extending the concept to a full range device.

Ion Tweeter

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