Roger, What you describe is an indicator of hardness at the point of impact, not them material's ability to transfer energy. You can achieve the same effect by alternately striking a surface with a hard hammer and then a soft hammer. The vibration spectra resulting from the impact of the hard hammer will contain more high frequency energy than will the impact from the soft hammer. But the induced waveform of each will reach the other side (end) of the pinblock sample in the same amount of time. (Well, almost the same time--the speed of sound through wood varies slightly with frequency; it decreases slightly with increases in frequency.) A more appropriate test, I think, would be to measure the length of time it takes for the induced wave energy to go from one end of the pinblock sample to the other when the sample is alternately struck along the edge of the glue lines and then on the flat lamina. (I'm assuming the glue lines would be those immediately adjacent to the point at which the flat lamina is struck.) ddf Delwin D Fandrich Piano Design & Fabrication 620 South Tower Avenue Centralia, Washington 98531 USA del at fandrichpiano.com ddfandrich at gmail.com Phone 360.736.7563 -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Roger Gable Sent: Tuesday, September 21, 2010 11:14 AM To: pianotech at ptg.org Subject: Re: [pianotech] YC Capo Bars Take a piece of pinblock stock about 12" in length, cut absolutely square in the other directions and then hit it with a hammer along the edge of the glue lines and then on the flat laminate. There is a difference is pitch. The laminate side produces a lower tone with the edge glued side a higher tone. Roger Gable
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