I'm not going to get into this whole buisness of whether or not an old soundboard can be just as easily and successfully used as a RC&S board again. I'll just quote the main RC&S guru around here from June 2001. He's citing an example Andre' posted about earlier that month... a late 1800's Grotrian that had been re-ribbed. While I understand that nothing much I have to say will likely be changing anybody's mind on this subject, I'd like to suggest that pianos such as Andre's Bechstein (was it?) upright with a re-ribbed original soundboard panel would sound about the same had the panel been replaced with one of the same thickness and mass characteristic made of new wood. It is now the new ribs that are supporting crown and forming the stress interface between the soundboard assembly and the string plane. I suspect the impedance relationship between the soundboard assembly and the strings would be about the same in either case. Regards, Del Then later in the same month of same year... in response to one of my posts in the debate... Ric : You just posted that a 100 or so year old panel with new ribs "probably" would sound the same as a brand new panel in relation to Andre's posting. A direct consequence of this reasoning (and the above) is that we dont need new panels at all. Just rip out any old panel from an old birdcage wreck...glue it back into one piece and rib crown it with new ribs and it will sound good as new. I am sure the soundboard manufacturers will be very pleased at this notion. Del : Yes, I did, didn't I? And, yes, all other things being equal, this is pretty much the case. After all, just what has changed during the life of that old soundboard, be it from an old birdcage wreck or an old Steinway grand? Longitudinally, (that is, with the grain) not much. There has been some nominal compression longitudinally, but not enough to worry about. Across-grain, though, we have a problem. There has been a lot fiber compression due to compression set and the old wood is now much weaker across-grain than it was when it started out. It is also considerably less resilient so we can't just dry it out and compression-crown the whole thing all over again. We'll have to do something about that. The thickness hasn't changed much unless somebody got carried away with their sanding. The mass hasn't changed much. So, once the original ribs have been removed what we have is a panel that is about the same longitudinally, but somewhat weaker and less resilient across-grain. Indeed, the panel might well have cracked and broken into two or more pieces. We'll solve these little problems by gluing the pieces back together and putting on a nice new set of crowned ribs. In this way we establish a new crown based on the curve cut into our new ribs, we establish some amount of cross-grain stiffness (dependent on the length, height and width of the new ribs) and remove the necessity to compress the panel across-grain to form crown. What we end up with is a rib-crowned soundboard assembly that just happens to use the original soundboard panel in place of one made using new wood. Makes good use of Earth's resources and the acoustics of either will be about the same. I particularly liked his last statement... in anycase.... since the man himself goes good for the basic premise reusing old soundboards in RC&S assemblies... I see no reasoning that contradicts what I originally stated that started this last flurry. Nothing wrong with using old wood in an RC&S assembly. I might add that the debate went on back then... Andre disputed that the sound of an old board RC&S and a new board RC&S would be the same... all else being equal as stipulated by Del. Del responded by agreeing... to my surprise... as that post directly contradicted what he wrote above.... The road goes ever ever on. Cheers god people of Pianotech. RicB
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