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How a horn amplifies sound (hint: Impedance matching)

2015-01-11

[public] 161K views, 4.72K likes, 59.0 dislikes audio only

A horn-shaped speaker is louder than an equivalent speaker without the horn. This fact doesn't violate physics because the horn is acting as a matching device between the speaker and the air around it.

Photo Credit for phonograph: Norman Bruderhofer, Collection of John Lampert-Hopkins