>>There's nothing wrong with beveled rims, but if you find no performance >>advantage to beveling rims and are building a piano, you wouldn't be too >>eager to spend the time to cut the bevel. > > I agree but there has to be some surface cut anyway flat or beveled > and As we've discovered through lengthy discussions some things are > easier than others to determine as to there actual performance benefit. > Stwy's diaphragmatic sound board design is a case in point. Murky water > perhaps but as I recall the treble edge rasten was raised to meet the > edge of the board so as to eliminate a bending strain by so doing. The > idea was that it freed up the board. You've put a couple of boards in Steinways. Have you ever found the treble edge rasten to meet the edge of the board in any of them without having to force the board down some considerable distance? >What's the proof? Probably subjective ears but hey we all do a good deal >of our authenticating that way I.e. improvements in raw hammers by >voicing, tonal improvements from new strings. In the case of the stwy >experiment the same type of subjectivity was used. Even if they used same >action in 2 different pianos the sound board wood is different, possibly >e.m.c.s'. I believe there concessus was it tonally better. I couldn't say. >You, Del or Ron O might have A different slant on these findings. I Bet you Do. Sure I do. They were making these subjective evaluations in exclusively compression crowned boards, in controlled conditions, over a very short period of time. That's a whole lot of limiting assumptions when you're looking for performance improvements in something that's supposed to last as long as pianos are expected to. Here's an onion, a pound of hamburger, a teaspoon of salt, and a can of chicken stock. Make bouillabaisse. > At any rate the best judge of that kind of subject determination in > my mind woud be the guys in the factory who were so familiar with the old > design compared to the new one that there opinion would carry some real weight I've always had a problem with this thinking. When would the guys in the factory working with the old ways ever get any experience with new ways to refine their opinions? What you will most likely get here is "This is the way we've always done it, so this way is best." And isn't that what we hear, for the most part? >>Why would you thin the board edges in the first place (except maybe in the >>bass if you don't float it), and why would it be less desirable to unduly >>stress these edges than it would a thicker edge. >>Tail thinning from the corner,around behind the bass bridge and clear up >>through the curve but leaving the top treble end thicker as you well know >>is fairly common practice in boards where tails aren't floated which is >>the majority of pianos that get restored in America. My personal >>experience is that thinning in these areas does provide a significant >>performance gain in sustain and clarity in conventionally >>reproduced belly systems. Meaning In my case rib crowned boards at 5 >>&1/2 to 6% emc That's why I said "except in the bass if you don't float it". To many folks, thinning the panel edge means thinning the edge all around, which won't do you any favors in the treble. Just looking for clarification. > I think it an important distinction to the readers on the list > that particularly You and Del are using techniques that are, at least in > some cases, a radical departure from conventional belly replacement. Your > focus is completly on belly redesign which is great and many will > hopefully incorporate your ideas and find out if this a desirable > direction they wish to go. Not so fast there. What you write about soundboard replacement indicates to me that you are doing considerable re-design work yourself. You are thinning panels in the bass, but not in the treble. You are crowning ribs, rather than compression crowning. You are laminating ribs. You are using sugar pine in the bass and spruce in the treble. You are using tighter rib radii than was originally evident in the bass (from compression crowning), and multiple radii - considerably tighter in the treble than in the bass. This doesn't sound an awful lot like accepting the subjectively arrived at wisdom of the factory guys relying on the time honored old methods to me. If any stress that can be avoided is undue stress, then any departure from traditional designs and methods is radical. You is in that category too Albert. >For some the tonal difference may not be what satisfys them compared to >what is considered good to them. Just as the tonal differences between traditional Steinway construction and what you are doing may not be considered good to them. How can this be determined before the fact just by the construction method and design? >Also every one has to start somewhere. The redesign cost could be a >significant impediment adding cost to an already pricey project. What's the difference in your prices between reproducing a compression crowned Steinway board (as exactly as you can), and producing a board with the design modifications you prefer? And incidentally, why do you prefer these design modifications over the original design? > It would be good for us who have heard much about the superior > design traits in these hybrid board systems to actually experience it for > ourselves. As yet I've not heard anyone weigh in on this illusive > experience. Being a sustain freak myself I'd love to hear the improved > sustain and color you both speak of. I've read comments on this list from folks who have heard examples of Del's work. Haven't you? I did take my first radical re-design prototype to KC, for a rebuilders' skills spot. It had some problems I've since learned to avoid, but the killer octave and treble wasn't among them. Go listen to Del's A. You're not that far away. >>Isn't Floating a tail simply a removal bending strains and stiffnesses >>caused by panel restrictions due to a clamped edge system? It's a lot more than that. It's disconnecting the panel from the rim altogether. >>How is a board stressed more by a rim beveled 1° less than the >>angle at which the rim meets the panel under load, than it is by a rim >>beveled 1° more? Doesn't compute. >> Ron N > > > I think you misunderstood my thought. Or maybe I did. The rim bevels > on stwys roughly equating 1 & 1/2 degrees will mate with a board in the > 60ft. crown range with no load. What I was trying to say was that a > lesser board angle due to string load might more closely match the crown > of the board under load. Yes I see your point though. Yep, bent up, or bent down is still bent. > It is however interesting as to how much faux crown can be exhibited > in an old board only to have it disappear completly upon it's removal > from the case. A condition or anomaly I attribute soley to the rim > bevel capturing the rib ends and panel edge. It does have some ,albeit, > small influence. Any way I don't dismiss it completly. > Regards > Dale Erwin That puts it in the realm of how much stress is undue stress. As you said, it's faux crown. Regards, Ron N
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