----- Original Message ----- From: "Overs Pianos" <sec@overspianos.com.au> To: <pianotech@ptg.org> Sent: December 08, 2000 11:38 PM Subject: Re: Grand piano design - parallel vs angled strike line? > To those commentators on piano design, and other interested lurkers, > > While it is generally accepted that the hammer strike line should be > parallel to the front of the key bed for smaller grands, the > situation is not so universally accepted for longer pianos. ----------------------------------------------------- Angled Strike Lines. In no particular order: 1) General German Stubbornness. I would guess that most current production concert grand pianos use this configuration simply because that is the way the Steinway is configured and since most of them are essentially copies of the D.. The Bosendorfer does not follow this practice because-if memory serves-it was designed before the D came on the scene. General German stubbornness has kept that design essentially the same since it was originally introduced just as general German/American stubbornness has kept the D design essentially the same since it was introduced. 2) Equal Length Keys. I have rebuilt at least two concert grands that were very similar to the D design with the exception that the bellyrails were parallel to the front of the keybed and the keys were all of the same length. In the two that I remember the overall performance was quite good but the principle pianists complained about the 'feel' of the actions in the treble section. In both cases there were complaints about repetition speed. Now, I don't know if these complaints were legitimate-i.e., that repetition was indeed a problem-or if it was simply that the feel was different than what they were used to with the typical D-type actions. I must say, I have never cared for the longer key of the Bosendorfer, but I' m not a pianist and am going strictly by tactile feel. I do a lot more work on D-type actions and it's not what I'm used to. 3) Key Bending. Key stiffness can be made whatever the designer and keymaker want it to be. All things being equal, however, the longer key will have somewhat more flex than will the shorter key. I have not done any specific tests on D-length keys. I do know we had enough trouble with one D action I ended up writing a couple of Journal articles about it. Yes, the C-88 hammer is »40% lighter than the A-1 hammer, but it still has mass. Add to this the mass of the wippen assembly and it will be enough to make the key bend. Clearly not as much as the bass hammers but some. As to how much of a factor this is, I don't know. Something makes a difference. 4) Key Inertia. I suspect this is more of a factor than anything else. If repetition speed is a factor it is probably because of the increased inertia that is inherent in the longer key. 5) Action Geometry. Sorry, I can't really see this as being a particularly important factor. True, the capstan-to-heel contact point is not perfect, but I doubt the difference can be felt in the real world. It is certainly not enough of a factor to warrant the complexity of tapering the heel and the consequent necessity of keeping the wippens is a specific order throughout. Remember, you have to consider more than just the manufacture of the instrument-someday it will have to be serviced as well. Additional complexity is fine if there are substantial-even noticeable-performance improvements. In this case, I doubt there would be. I think you are right in that most actions seem to be set up for the treble. Probably because most designers and builders consider the treble to be less forgiving and critical. In reality, the action should be optimized around the bass/tenor break, or there about. 6) Soundboard Area Behind the Bridge. This can be anything the designer/builder wants it to be. As several have stated, there is not much point in going through the design process and retain the constraints of the original package. New rim presses are not that difficult to make. Even the vary large, highly automated presses work around a replaceable caul. I don't think cost is the factor here. It is more tradition, fear and self-imposed marketing constraints. "We've been doing it this way for over a hundred years." Or, more to the point, "Steinway has been doing it this way for over a hundred years, and when Steinway changes, then our R&D department will discover that some new configuration really would have been better all the time and then we'll change. Of course, if it turns out to closely resemble the change Steinway just made, that will be pure coincidence." The 'fear-factor is also a strong constraint on development. "We know this works, we don't know something different works." A century back, piano companies were run by piano makers, today they are run by 'business' people. Both are clearly required for a piano maker to be successful, but in many companies it would appear that the business side has had to much control for to long. Finally, there is little marketing incentive to try something really new." Check the four-colored glossies. At least as much dialog goes into marketing tradition as anything else. I have gone through the experience of being told that a change that clearly and demonstrably improved performance would not be made because it would negate a tradition of marketing that went back (at the time) some forty years. Marketing was afraid it would make them "look foolish." (Their words.) Anyway, the rim shape can be whatever the designer wants it to be. With or without the angled strike line. 7) Dead Space Between the Capo d'Astro Bar and the Stretcher. Yes, this could be a factor with making the strikeline parallel to the front of the key headscale. But, clearly, not a compelling one. After all, Bosendorfer does this all the time and I've not heard many complaining about arm fatigue due to the longer stretch. I would also worry about making the string segments longer just to position the tuning pins closer to the front of the piano. In fact, I wouldn't do it. I prefer to keep these string segments as short as is practical. This does make the pinblock somewhat large and expensive, but at the prices Bosendorfer asks for their pianos, I doubt this is a factor. 8) Building, or Assembly, Complexity. This may be a factor for a one-off, or a prototype instrument, but not in production. True, one company clearly has had a problem with action geometry over the years, but this is due to the assembly sequence and process, not the design. When the plate location is made a variable, things get impossibly complicated. But, despite colorful prose to the contrary, modern pianos are not 'built by hand.' Not even in small factories. They are built by semi-skilled (ok, sometimes skilled) workers, cutting, fitting and assembling to jigs and fixtures. Larger factories work to the x,y coordinates controlling their machines, and the machines don't care at all about things like cutting angles. All other factors being the same, it is no more difficult to build a piano with an angled strikeline than it is to build one with a parallel strikeline. 9) The Fandrich Vertical Piano. With due respect to my brother, Darrell-who designed the action used in our piano, he was not involved in the design or the production if the Fandrich Piano. 10) Drilling Through the Soundboard/bellyrail. Yes, several piano builders have used the technique of drilling through the bellyrail and soundboard for damper wires. The several I have seen over the years had drilled through the soundboard liner and not through the speaking portion of the board. This is an issue I have not yet resolved for myself. Our 122 Vertical used 72 dampers, and all of them were necessary. Obviously, it is quite easy to extend dampers up a ways in a vertical, more so in a grand. Still, it is not impossible to design for 72 dampers without the complexity of drilling through the bellyrail. I have problems with excessive design complexity-having frequently been found guilty of such-since it is difficult to get this complexity built properly without throwing lots of money and time at it. This area is always going to be a compromise between the ideal-which is impossible to achieve-and the practical. 11) Compromise. If anyone ever tells you that a piano is either designed or built "without compromise," they are either lying to you or they simply don't understand what they are talking about and should stay out of the discussion. Regards, Del
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