> *But wouldn't the string plane > only push the board until the string plane itself flattened out*?. > > /_Yes ! Of course_/ No, not really. I've measured both negative crown and negative bearing in a lot of killer octaves that still had a bunch of bearing in the treble. That third class lever effect I've talked about, with the treble end as the minimally deflecting fulcrum, can and does lever the killer octave, which is in the extreme bend of the bridge, and gets no beam support from down scale like it would with a straight bridge, into negative bearing and crown. > I'm guessing that negative crown with negative bearing would produce > the same pair of opposing springs (board panel plus string plane) > that we all grew up calling home, with positive crown and positive > downbearing. You'd enjoy the same mechanical advantage either way. > (You'd just have to toss out bridge pins as a coupling mechanism.) > > /_Seems right_/ No reason it couldn't work, if it was designed to be that way. It's unlikely that you'll find a piano designed for positive crown and bearing that will sound good through a full dynamic range in this condition. > Ladies and Gentlemen, over in this corner, wearing the purple > shorts, we have...." a no crown no bearing piano that works, but > still sounds somewhat different than we're used to, which isn't > necessarily bad........ > > .........but not something I'd bet on when it goes up against the > reigning champ, a crowned board ("Spring'o'Spruceâ„¢") with > appropriate > bearing. > > _Yes I agree. I once tuned a miserable 9 ft kawai that never really > had any fire in the tone . Then one day, when I had time to kill ,I > checked the bearing with a lowell gage . ZIp, nada nothing. I used a > crown string to look at bearing.. Massive Crown. No bearing. Moral of > story. The car looks good but there is no gas in the tank . The same > is true of springy spruce with no bearing. Looks good but it doesn't go > very far._ > Dale And I was, of course, talking about something designed and built for zero bearing and zero crown throughout, not something that was designed for positive bearing and crown and badly built. Ron N
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