All, >----- Original Message ----- >From: "John Delacour" <JD@Pianomaker.co.uk > >> At 11:54 18/09/01 -0700, Delwin D Fandrich wrote: >> > > >While I acknowledge that many pianos do have the drop-off you mention, it >is certainly not desirable. Most of these (obsolete) scales do much better >with several bi-chord wrapped unisons in the tenor section ideally placed on a > > >separate bridge. >> >> Interesting. On the one hand you bemoan (as I do) the characterless >> uniformity of modern piano tone and on the other you talk of "obsolete >> scales" (which I think would include all Steinway's grand scales?) and yet >> you talk of an ideal solution lying in a transition bridge, which was >quite >> common in the 1870s - 80s and universally discarded in Europe before the >> turn of the century, roughly speaking. I'm not disagreeing with you but >> I'd like to know what classes as an obsolete scale in your view? > >To pick just one example the S&S B scale is, in my opinion, an obsolete >scale. C-88 varies between 47 mm and 49.5 mm which is some short by today's >standards. The bass/tenor break (at E-20/F-21) falls to low in the scale for >a piano of this size resulting in either an excessively low string tension >(approx. 120 lbs, depending on the bridge location) or excessively large >diameter strings to keep the string tension in line with the higher scaling >(it would require a 0.053" string to keep tensions in the mid-160 range). Exactly Del, and even when a thicker wire is chosen to keep the tension higher, the percentage of breaking strain will remain low therefore maintaining poor tuning stability. >The only practical solution without changing the plate is a third or, as you >call it, a transition bridge. (Good name, that.) Given a transition bridge, >the upper bass bridge >is still placed such that the bi-chords are considerably shorter than I >would like to see them. > >> For >> example, would Klauss Fenner's ubiquitous scales be classed as modern and >> therefore productive of a tone quality that is more desirable than that of >> the great pre-1914 pianos? > >I don't know enough about Mr Fenner's scaling practices to comment on them. >I have, of course, looked at them and they seem pretty traditional--that is >obsolete. And the small grand piano scale described in his latest book >appears to have some (again in my opinion) pretty serious problems. But I've >not really done any in depth analysis of any of them. Perhaps others would >like to comment. Some of Fenner's scales are a moderate improvement on some earlier scales, but they mostly go about half way towards an optimum solution, as do Yamaha with their C7F. Actually, when I look at the design of the Samick 225, I can't help suspecting that they might have had a C7F sitting next to the drawing board while 'development' progressed. While there are many differences between the Samick and Yamaha designs, the scale isn't one of them. The F21 break of the traditional 7' class pianos is nothing short of a scaling disaster. Yamaha's earlier C7s bear this out also. Now that they've moved the break to G#24 in the C7F, its better but still a few notes short of where it should be. Check out the latest Blüthner model 2 (7'8"). It's a very good scale with a 26 note bass. >(JD)> As to the fall-off in tension at the extreme treble, obsolete or not, I >> would always aim for this; not to do so is asking for breakages in view of >> the doubtful quality of modern wire. To expect a No 13 wire to support >> 170-180 lbs. is, I think, optimistic, and I would set the length of note >88 > > at 4.8 - 5.0 mm. the tension to rise with the gauges to an average 165-70 > > lbs for the remainder of the steel scale. > >(Del) I expect you mean cm in the above. And I disagree. Me too Del. >Many, if not most, modern >pianos are running upwards of 52 mm at C-88. Many are in the 54 to 56 mm >range with no long-term undesirable side effects. My own standard is C-88 = >54 mm. Agreed, I use 53 as our standard for C88. > >(JD) As to the lowering of tension at > > the other end of the long bridge, you seem to be saying this is a sign of >> obsolete scaling and that seems to mean that most modern 6' grands have >> obsolete scaling, > >Yes. That is a good summary of what I am saying. Totally obsolete. The quicker this ordinary design practice is dropped the better. There is not a decent 6' scale made by anybody at this time. > > ...since the only ways to avoid this are a) to shift notes > > onto the bass bridge, which would cause even worse problems I absolutely disagree. There seems to be some fear of placing more notes in the bass section of shorter piano scales. The cross over point should be determined by the maximum speaking length, and should not be considered from any traditional standpoint. Let's start thinking laterally, instead of fearfully looking over our shoulder at what's gone before. > > I've seen uprights with 5 bridges, all at different levels.. >> there's something that _certainly_ won't return! > >No it won't. Nor should it. My latest 200 cm design uses a transition bridge >although the scale only has one break. That is, the tenor/treble bride is a >true semi-log scale from C-88 down to the transition between the tri-chord >plain strings and then it transitions to the bass (bi-chord wrapped) which >is also a semi-log progression. (I hope that makes sense--it's easier to >draw!) > > > >> >So far I have found no rationale for the use of tri-chord wrapped strings >on >> >either bridge on any scale of any length. >> > > Presumably the rationale is not only to aid the transition but to produce > >a certain quality in that section of the piano. One of my favourite > > instruments of all time is the old (ca. 1899) Steinway 6' grand. The bass >> bridge and scaling on this piano up to note 20 are almost identical to the >> 6'2" model A that succeeded it, but as you know there is then a transition >> bridge holding two covered bichords and 7 covered trichords. The A has >> only two bridges with 5 covered bichords on the long bridge. There are >> other differences of course, not least the fine quality of the soundboard >> on the older one, but personally I find the 6' piano magic and the 6'2 >> relatively uninteresting. It's a while since I have had my hands on >> either, but I think this is a case where covered trichords actually served >> a purpose and were not a mere fudge. August Förster until quite recently, >> and maybe still, used several trichord break notes on their uprights but >> this always struck me as either a bit of show or a necessary fudge to hide >> bad scaling. > >But this practice is always a fudge. Exactly Del. There's no justification for using trichords on the transition bridge. The tenor bridge 6' Steinway was a better scale than the modern thing with the bichords on the long bridge. But the newer scale is just a fudge like all the other current crop of boring 6' grands. Ron O -- ______________________________ Website: http://www.overspianos.com.au Email: mailto:ron@overspianos.com.au ______________________________
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