I'd agree with your summary, Roy: a firmer attachment, keeping more energy in the strings. It says here (http://www.wapin.com/overview.htm) that "more energy is reflected back to the string, creating less of a dampening effect than the traditional arrangement"... "The traditional way of installing angled bridge pins at the first termination point...appears to provide a stronger than necessary coupling. This strong coupling takes large bits of the mechanical energy in the string, before it even has a chance to convert itself to harmonic energy (first 30-60 milliseconds), and dispenses it as attach noise. The Wapin technology, in contrast, de-couples slightly the energy between the bridge and the soundboard...". I'd type more of the liner notes, but they're copyrighted. A key point is "a vibrating string in a piano takes on a substantial movement in the unstruck direction shortly after it receives the blow from the piano hammer." Apparently this bridge was covered in the Piano Technicians Journal, Jan. 1999, pp. 31-34. The (very large) link to the patent is: http://164.195.100.11/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=/neta html/search-bool.html&r=1&f=G&l=50&co1=AND&d=ft00&s1=wapin&OS=wapin&RS=wapin --Cy Shuster-- Rochester, MN ----- Original Message ----- From: "Roy Peters" <roy.peters@mindspring.com> To: <pianotech@ptg.org> Sent: January 24, 2002 12:02 AM Subject: Re: Sound waves(The behavior of soundboards) > Does it really say that the system acts as a resistor? As I understand Wapin, > the idea is that less energy bleeds off as attack noise. A slanted pin dampens > the string. Moving the front pin to a vertical position lets the string ring > more freely. I will have to read the liner notes again, but I think that this > is what was meant. > > Roy Peters > Cincinnati, Ohio >
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