Though the "Chaldni" misspelling is fairly common, the correct spelling is
definitely CHLADNI.
Also, Ernst Chladni (1756-1827) certainly wasn't living in 17th century !
BTW, I found recently a website promoting a "Modal Synthetiser", which is
actually an electric Chladni plate. Costs 225 $. See :
http://www.regencynet.com/modal/index.htm
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Jean-Pierre Lentin
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