Ron makes a good point here, I saw a rebuild in a concert Grotrian Steinweg done in Sydney Australia by Ron Overs, where the front duplex was too long and produced a frequency low enough to be a real problem. His fix involved putting in a small pressure bar. This roughly halved the speaking length of the duplex thus raising the frequency produced by this section to a point well above the problem. This was all done without reducing the energy of the main speaking length....no compromise to the tone of that section. Mark Bolsius Canberra -Australia ---------- From: Ron Nossaman <nossaman@SOUTHWIND.NET> To: pianotech@ptg.org Subject: Re: S&S capo Date: Mon, 22 Feb 1999 3:24 AM It is a string termination problem, but it's at the capo. If there isn't sufficient string bearing angle across the pressure bar (about 20 degrees), there will be a lot of energy leakage into the front duplex, as you have noticed. This is a design problem resulting from an attempt to get better sound out of an area in the scale that can't produce the sound because of another design problem with the soundboard. Reshaping the pressure bar may help, or may make it worse, but the fact is that it was intended to make noise. Other pianos won't make exactly the same noise because they don't have exactly the same configuration of bearing angle, duplex length, and pressure bar shape. This was all discussed at great length some time back. You might check the archives. Ron
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