> The other possible suspect is loose bridge pins. Earlier I had noticed > a consistent drop around A6 on some strings, and found I could slightly > move a few leading bridge pins with screwdriver pressure. How this > would lead to pitch drop, I'm not exactly sure... > > --Cy Shuster-- I don't think that has much to do with it at all. I've noticed this sort of thing with Yamahas for a long time now. Tuning these pianos, I've found that a firm rap on the key will very often result in an unusually dramatic pitch drop. Tuning in a more usually non-violent manner that will usually suffice with other pianos, in my experience, will leave the Yamaha in a less stable condition. There seems to be an increased tendency for the string to render through the bridge pins easily in these pianos, so you have to encourage the tendency by whacking them at least once to force the issue. Otherwise, the rendering will happen shortly after you've gone, and will be putting up billboards as a public testament to your inability to handle this "condition". I've followed a number of otherwise quite competent tuners through the years, who failed to whack the rendering/pitch drop thing appropriately, and left a piano that went badly out of tune within the week. It ain't hammer technique. It's what's happening at the bridge, and string segment tensions. Ron N
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