<!doctype html public "-//W3C//DTD W3 HTML//EN"> <html><head><style type="text/css"></style><title>Re: [pianotech] Tuning the duplex sections</title></head><body> <div><br></div> <div>A propos of nothing in particular, I mentioned the other day the sloping wrestplank on certain 19th century pianos as illustrated below</div> <div><br></div> <div align="center"><img src="cid:p06240803c9a68c180652@[192.168.1.66].1.0"></div> <div><br></div> <div><br></div> <div>and mentioned that the angle is 8° and that the bearing cloth serves as little more than a damper for the front section rather than a bearing as such.</div> <div><br></div> <div>This design seems to have several advantages from a mechanical and tuning point of view over the design that followed it and persisted for many years.  Contrast this with the arrangement on a classic Bechstein grand where you have a beech bearing up to 3" wide covered with a thin bearing cloth -- sooner or later it becomes extremely difficult to tune these owing to the friction at the bearing combined with oxidation of the strings.  With the old arrangement the pressure on the bearing/muting cloth is minimal, but it must have very similar characteristics to a front duplex that is listed or otherwise muted.</div> <div><br></div> <div>The reason why this old design died out might have something to do with the development of the full metal frame with integral wrestpin plate, but I can't see any practical difficulty in making a casting to follow this design.  The other possibility is that makers decided this arrangement was tonally inferior to the design that followed it...</div> <div><br></div> <div>...On pianos of the next long-lived generation with agraffes, which is to say almost all pianos except Steinway copies, the bearing is brought so close to the agraffe that you often need to kink the wire when pulling it through in order to avoid nicking the bearing cloth.  In other words there is only a very small length of wire between the stud and the bearing, so that there can be no appreciable leak of energy across the bridge and the bridge becomes as closely as possible a true termination to the speaking length.</div> <div><br></div> <div>The case of the studded upright is similar in effect the stud provides for a fixed angle and an extremely short length between the bridge and the string holes.  In my experience the tone of that minority of uprights that have studs all through has always been good, though uprights with studs always to come from makers that are pretty good in the first place.</div> <div><br></div> <div>This topic has got me questioning certain ideas that I've held, or been developing, for a long time.  The primary consideration must always be optimum tone.  If a certain design makes it easier to tune or more durable, well and good, but if a design that has advantages is to the slightest detriment to the tone, then tonal considerations must prevail, I think.</div> <div><br></div> <div>JD</div> </body> </html>