Terry, It's not just a killer octave, it starts in the bass side of the first capo area and extends into the tenor area and up towards the treble. It some cases its the whole middle of the pianos that is killed. As pianos age the soundboard no longer supports the full amount of bearing. This will happen to any piano no mater how it is made. Some techniques and designs accelerate the process and some designs delay it. Even the very best designed and crafted piano will eventually fall victim to the disease. Poor craftsmanship will certainly contribute to this problem and many pianos leave the hands of rebuilders and manufacturers with dead soundboards. I have visited shops were no control of relative humidity prior to ribbing assures that the soundbaord will have practically no crown at all. The hapless craftsmen at these shops seem completely un bothered by this result but a soundboard without adequate crown is doomed to tonal mediocrity. It is notable that this problem happens on virtually all modern pianos. This indicates that the problem is not caused by scale designs or ribbing patterns or many of the other possible causes but is inherent to all pianos that use string bearing to raise the impedance of the soundboard. Why does it start and spread from the low treble? This area of the scale, in my experience, relies on bearing pressure to create a round tone more so then other areas of the scale. It is also an area that receives more pressure from the bearing than lower down in the bass. I got into this in more detail in my downbearing articles published in the fall of 95. Some people expressed surprise at the high numbers I calculated (in the article) for the bearing force on a new soundboard. Even after seven years I am still convince of the need to apply adequate bearing in this area of the scale. Obviously precaution need to be made to assure a reasonable life span for the soundboard. This is were craftsmanship plays a major role; making sure the panel is strong with good glue joints, seasoning and selecting spruce for the panel as well as dimensioning the ribs and profiling them with adequate crown. And, of coarse, making sure that the soundboard has true crown both along the ribs and along the bridge. John Hartman RPT John Hartman Pianos [link redacted at request of site owner - Jul 25, 2015] Rebuilding Steinway and Mason & Hamlin Grand Pianos Since 1979 Piano Technicians Journal Journal Illustrator/Contributing Editor
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