117 This professor bounces sound waves carrying music that can not be heard out loud but can be heard in. (m.youtube.com) posted 1 year ago by GGRockz 1 year ago by GGRockz +117 / -0 43 comments share 43 comments share save hide report block hide replies
that's pretty weird.
So I guess you only hear it if you're in the very narrow angle of the beam.
Wild stuff.