I think I understand it a little better...mechanical energy transformed into sound energy... David Ilvedson, RPT Pacifica, CA 94044 ----- Original message ---------------------------------------- From: "Delwin D Fandrich" <del at fandrichpiano.com> To: pianotech at ptg.org Received: 5/18/2009 12:15:19 PM Subject: Re: [pianotech] FW: RE: New Ask Physicist question >| -----Original Message----- >| From: pianotech-bounces at ptg.org >| [mailto:pianotech-bounces at ptg.org] On Behalf Of Stéphane Collin >| Sent: May 18, 2009 9:05 AM >| To: pianotech at ptg.org >| Subject: Re: [pianotech] FW: RE: New Ask Physicist question >| >| >| - If we talk acoustic pressure level, the one caused by the >| strings is very low, due to small surface of the strings and >| huge short circuit effect of the air surrounding them when >| they move. The one caused by the driven soundboard is much >| higher, even considering the reduction of kinetic energy >| after its transfer from the strings to the soundboard, >| because of its large surface. So, one can say that the >| soundboard is an acoustic pressure amplifier of its driving >| strings. Not ? >No, not. It is not "sound pressure" produced by the vibrating strings that is >causing the soundboard to vibrate and produce a greater "sound." It is the >mechanical energy in the strings that is being transformed, or transduced, into >sound energy. Mechanical energy (vibrations) is coupled via the bridge to the >soundboard assembly where, by the forced motion of the soundboard assembly >(still in the form of mechanical vibrations), sound energy is produced in the >surrounding air. Nothing is amplified. >ddf
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