<blockquote style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;" class="gmail_quote">My curiosity along those lines concerned tuning stability, and how dimensional change in bridges and soundboards, or how much rendering across a bridge accounted for what we hear in real pianos. I expected a moderately accurate proportional indicator, rather than a three decimal point absolute. List discussions seem to be thick with binary all or nothing arguments, but I live somewhere well in between.</blockquote><div> Ron,   I think I may have found a kindred spirit :) Beyond my simple thirst for knowing why, my interest here lies in trying to figure out what I am actually doing when I find a stable resting place for a member of a unison. My goal is to distill a belief based on reason and evidence rather that myths that somehow seem to work, as if by magic. We are not scientists, but I feel that much can be gained by taking a few minutes and pretending we are. For me, the issue of pin movement is a good place to start, although it is only the tip of my current set of ideas for real-world experimentation. If you would like to share ideas more fully, I would enjoy continuing this discussion through email if you want. Let me know. (and as far as the original question goes, I have also posted it on a physics forum, so I will let you if they have anything to say to clear things up) Thanks,   Kurt   </div>