Helmholtz' Continuing Resonance

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Hermann Ludwig Ferdinand von Helmholtz (August 31, 1821 – September 8, 1894)

    Hermann von Helmholtz was a physician and physicist who, like most scientists of his era studied, researched and invented across a broad range of subjects, from the physiology of sight and colour vision, to the perception of sound, acoustics and electromagnetism.
    What is not widely reported is his influence on the sound of reggae.
    In the field of acoustics there is one stand-out invention that in some form or another has moved many a person - on the dancefloor, at parties, or just at home - to dance. The Helmholtz Resonator, or at least it's distant cousin, the bass reflex loudspeaker. Although larger and outdoor venues demand a different approach to bass sound reproduction, the bass reflex was, in its day, the sound of reggae; characterised by deep, powerful, loping basslines that hit you in the solar plexus like a punch from a heavyweight fighter.
    The principle of the reflex cabinet is deceptively simple. Like all speaker cabinet design, the bass reflex has a principle function to perform: to undo the bass-sapping effects of cancellation and drive-unit resonance. Armed with appropriate equations and specifications, known as Thiele-Small Parameters (Google 'em) you can tune your speaker box to create maximum mayhem with minimum effort on the drive-units part. Musical bliss ensues.

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