Illustration of Faraday wave

1831 Faraday wave

The book of science

Tom Sharp

Michael Faraday acoustics Illustration of Faraday wave

Faraday wave

Michael Faraday wasn’t the first to study vibrations on surfaces. Robert Hooke studied “nodal patterns” on glass plates and Ernst Chladni studied eponymous “figures.” Accoustic waves on the bodies of musical instruments. Fountains of agitated water in a vibrating singing bowl. Faraday demonstrated that powders on a plate are affected by currents of air as well as directly by vibrations of the plate showing equal divisions of the surface drawn by curved lines and heaps of powder at the points of greatest vibration. Faraday also experimented with various liquids, observing that vibrations overcame the force of gravity and presented regular and permanent “crispations” whose sizes corresponded to the frequency of vibration and to the depth of fluid. Patterns of powder on a vibrating plate or membrane. Standing waves on a liquid surface in a vibrating container.

Good standing

People still make guitars and violins by ear, adjusting the narrowness of the waist, sanding thickness from the belly to improve symmetry and resonance. The materials, the shape of surfaces, the size and shape of the enclosed cavity and many things known by experienced craftsmen, handed down from teachers and masters, have been proven to work.


I hope I can get on the record saying this stuff is hokum, except to the extent that it makes some people feel good, and as long as it causes no harm, directly or indirectly. People think they can believe anything they want. They think facts and truth don’t matter with respect to faith. Well, I hope I can get on the record, saying this stuff sounds nice and it sounds beneficial, but in fact it’s delusional. It’s a lot like a sugar pill.

You can achieve accoustic excellence without understanding the mathematical formulas that describe it; however, many spaces are designed with other priorities in mind.

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