>Hi Ron, > >I have posted about it before. Full perimeter plates and individually tied >strings are where I have noted less than usual pitch drops. One piano in >particular comes to mind, the Baldwin 6000. Plate flex at or near the hitch >pin may be less with one hitch pin per wire, even though the total tension >on the plate would be very similar. It would seem logical to assume the >hitch pin itself would bend less with only one string tugging on it. Yo Don, Full perimeter plates, I can logically account for - all other things being equal. The individual hitch thing, no. Unless you're talking about vertical hitch pins, the bending of the pin isn't a significant player. Even with vertical pins, unless they're too small in diameter, pin bending isn't worth noting, since pulling up adjacent notes wouldn't bend pins on already tuned notes and make the pitch drop - now would it? Strings set too high on vertical pins could, would, and do torque the plate excessively, and would have an affect. A big flat hitch pin field is necessary for all those pins though, and on some pianos that might translate to a plate that has a wider expanse of iron parallel to the string plane between struts, making the beam deeper and resulting in less deflection, but that's not necessarily the case, and really doesn't have anything directly to do with the individual pins. Next time, look at the length, width, and thickness proportions of the iron between the struts instead of the pins and see if there's a correlation to pitch drop. That's where it's happening. We can say this piano does, and that piano doesn't all day long without clearing up anything. There are good solid, relatively simple physics based cause and effect relationships at work here. Ron N
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