Hi Del, Thanks for the detailed response. I had just a fleeting look at the instrument: when I was leaving the dealership after evaluating pianos for a purchase, running late for my next appointment, the dealer tech said "You've got to take a look at this before you go." So I spent less than five minutes, enough to look at things and run fingers up and down the scale and think "This isn't bad , not great but maybe some potential." The tech said it was originally sold by a local dealer who wasn't much on dealer prep, and that the owner said no piano technician had ever darkened his door (never tuned after the free dealer tuning), so it was, shall we say, in fairly raw condition. Something that puzzled me: why a solid maple bridge rather than the standard (for Baldwin) vertical laminated? I was thinking that if I designed a bass bridge that way, I would want it to be laminated for stiffness and stability. But both treble and bass bridges were solid maple with solid caps. I suppose I know the answer: production cost. Regards, Fred Sturm University of New Mexico fssturm at unm.edu On May 1, 2008, at 8:58 PM, Delwin D Fandrich wrote: > The B is one of my designs. At least the original was. When built > well -- which > was seldom, if ever, the case -- it was a decent little piano. The > undercut bass > bridge is one way of coupling the vibrating energy from the strings > to the > soundboard in an area with just a bit more mobility than it would > have had if > the bridge contact were right up next to the inner rim. It takes the > place of a > cantilever by moving the contact point of the bridge out away from > the inner rim > without introducing the rock and roll motion of the cantilever. Did > it work? > Well, yes, for the most part -- keeping in mind that the piano also > has a > laminated soundboard that is just a bit too thick for that area. > Everything is a > compromise. The low bass performance is certainly better than it was > with a > cantilevered bass bridge. (Yes, I tried both.) > > Could it be done differently with still better results? Perhaps. > Were I doing > another piano of that size I'd now do it differently. If you've > taken one of my > all-day seminars recently you might have a CAD drawing of how I > would have done > a piano of that size in the late 1990s. It's on the last page or so > of the > hand-out. And I've moved on a bit since then. > > This stuff has its greatest value in small and very small pianos. > These -- > assuming even moderately sensible design -- are the only pianos > where the > cantilever shows up. With very few exceptions the backscale in > larger pianos > (say from 200 cm on up) is long enough, and the bridge contact point > is far > enough away from the inner rim, that cantilevers are not used. Even > in the 185 > cm to 200 cm range where cantilevers were used in the original > design they can > be dispensed directly without much, if any, major surgery. > > It's from there down that the problem of the ever-shorter backscale > begins to > significantly impede bridge motion and low bass tone performance. > But even here > everything is relative. If the backscale length in the low bass > averages, say, > 100 mm, making it 20 mm longer will give the low bass a noticeable, > but probably > not dramatic, increase in clarity and pitch definition. After all, > you're only > making the backscale length 20% longer. And the low bass performance > should > already have been at least reasonable. > > Increasing the backscale length from 25 mm to 50 mm, however, is a > 100% > increase. And decreasing the cantilever overhang by even that much > will > substantially improve its energy coupling efficiency. The > combination will give > you a dramatic improvement in low bass clarity and pitch definition. > Even > considering that we have made the speaking length of the string 25 > mm shorter. > Most pianos in the 150 cm range will have an A-1 speaking length of > around 1,100 > mm (give or take some). Making this 1.075 mm, or about 2.3% shorter. > I doubt > anyone could hear any tonal difference that could be attributed to > this amount > of change in length. Will this piano end up with a great sounding > bass? No, > probably not. But it will be a whole lot less bad than the original. > > There are a whole lot of pianos out there in the 150 cm to 180 cm > range that > have low bass backscales in the 25 mm to 40 mm range. (Remember, > it's the > effective backscale length we're talking about. Not the physical > distance from > the back bridge pin to the c/l of the hitch.) Most of these pianos > have > extremely short backscales and their bridges are all mounted firmly > on a floppy > and lossy cantilever. In my opinion they can all be given a more > pleasant-sounding low bass by lengthening out that backscale and > shortening up, > or removing entirely, that cantilever. > > ddf > > > | -----Original Message----- > | From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On > | Behalf Of Fred Sturm > | Sent: May 01, 2008 5:52 PM > | To: College and University Technicians > | Subject: Re: [CAUT] Bass bridge, string scale, cantilevered > | bridge, tone > | > | The answers to Alan's question I have read don't really deal with > the > | topic: an especially short scale instrument. On the topic, I > | happened today to see a Baldwin grand from around 1995, I > | think it said model B with a number after it, not something I > | had ever seen. It was a 4' 11" > | or so, and had a bass bridge without apron or cantilever, and > | the bass end almost touched the plate, but was undercut for > | the lowest eight unisons (not contacting the soundboard). I > | guess that is one way to do something or combination of > | things. It did have accujust pins so that probably helped > | matters. Not too bad a sound. Not too great either, but it > | could have used some voicing, so maybe there was potential. > | But to Alan's question, there does seem to be a > | tradeoff when you get to a really foreshortened scale. Would > | the sound really be better if you foreshortened the scale > | more in order to lose the cantilever? (No argument about > | changing to German loops - that's likely to be an > | unquestionable improvement). It seems like a tradeoff between > | what the string is producing and how the soundboard is > | transmitting, and if the input from the string is bad enough, > | the better transmission isn't going to make for a better > | overall sound. That's just pure "logical thinking based on > | limited experience in related matters." Could be dead wrong, > | but I think what Alan wanted was experience in this realm of > | the mini-scale, and I haven't seen it addressed: will the > | bridge change with the corresponding shorter scaling be > | capable of a better overall sound, worth the trouble? > | Regards, > | Fred Sturm > | University of New Mexico > | fssturm at unm.edu > | > | > | > | On Apr 30, 2008, at 2:18 PM, Alan McCoy wrote: > | > | > Hi Jim and Ron (and others), > | > > | > I do not have enough first-hand experience with especially > | short-scale > | > instruments that have been recipient of the kind of > | treatment that the > | > Brodmann thread was about, namely new string scale with a shorter > | > speaking length, longer backlength, no cantilever. But I am > curious > | > about what kind of tonal change I might anticipate if I were to > | > rescale, say, a Kawai GE-1. > | > > | > Would anyone be interested in describing what would be the likely > | > tonal result with these changes to this short-scale piano? I know > | > words won't likely do justice to it, but I'd be interested to hear > | > anyway. > | > > | > BTW, this isn't idle curiosity. > | > > | > Thanks. > | > > | > Alan > | > > | > > | > -- Alan McCoy, RPT > | > Eastern Washington University > | > amccoy at mail.ewu.edu > | > 509-359-4627 > | > 509-999-9512 > | > > | > > | > > | > > | > | > >
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