Roger Hill

You're right, Jim, they are very different forms. But evidently, Tony and Joe were trying to do the same thing to the grads. There must have been some reason for that. Otherwise, I think we would see what lots of modern makers espouse, all over even thickness.

I am sure they do sound different, Oded. But I trying to figure out what they were thinking that led to the similarity between three violins done over a span of forty years. To me, it looks as if all three were done with thinning of an "X" pattern with the cross of the "X" at the center of the violin. But what one would be trying to accomplish with such a pattern I can't intuit. Also, Oded: it is common to see a graduation with a very thin spot right on the edge. Do you interpret these as places where the maker did some outside tuning? Thanks,

Usually, the Loen maps of plates are viewed from the outside, sound post on the left side of the back. He states this in the article about the del Gesu violins. Another really interesting violin is the Nicola Bergonzi violin shown by Hans Pluhar on his website http://www.hanspluhar.com/bergonzi_progress.html Reminds me of the Cannon that is shown in the del Gesu link. Incredibly sharp transition between thicknesses along the ridge of the spine on the back.

corrected Betts link. Dean, use dryfly_6x at msn dot com if you prefer. Thanks

Not in my way of thinking. I see it as a variable stiffness with an increase at the anchor points. Thanks, Dean. Tell me what you mean by anchor points and what they do.

Hi everybody. Every time I study a graduation map I come up with more and more questions. Please take a look at the top graduation maps of three violins shown in these sites: the Harrison Strad, 1693 http://www.fiddleheadstrings.com/fiddlehea...b_mar06_008.htm the Betts Strad, 1704 http://www.catgutacoustical.org/journal/nov02.htm the del Gesu Kreisler, 1733 http://web.archive.org/web/20071031155409/...p;path%5b%5d=42 The similarity of the top graduation patterns is really remarkable. Looks as if the makers both had the same thing in mind as they were scraping these plates. For those of you who know about the two Strads, do they have very low arching similar to the Kreisler? Perhaps very shallow flutes at the edges? Other similarities come to mind? Does anyone suspect that the thinnings in the upper and lower bouts were to give a uniform stiffness all over the top plate? To move the center of mass nearer to the bridge? Any other SWAG's? Also, if others have bookmarked links to Jeff Loen graduation maps for other violins, I would really appreciate it if you would post the links here. I have the Strad project DVD already. Thanks,

No, I'm paraphrasing Zygmuntowicz here. Got out the book and checked again. The whole quote is: "This material that I'm using, I feel like it just crawls into the wood and becomes one with the wood. This spruce was so soft and powdery when I worked on it---this ground is going to glue all those fibers together. It's not glue per se, but it'll have that effect. It's going to make the surface of the wood feel stronger, and hopefully that will make the material even more responsive to the tiny little vibrations. It'll have more of that sizzle-y kind of vibration when it's played, which gives a more complex, shaped sound." My memory was less than stellar regarding the hazardous bit: "I'm not sure OSHA would approve of my material-handling techniques, but I'm a ravening beast when I varnish" Regarding the heat lamp: I'm kind of melting it into the violin. This needs to happen with time, but you can get a little head start with this lamp. I'm almost cooking it in, really impregnating the wood" Then Marchese, the author, comments that "As he worked, little wisps of smoke floated out of the violin through the f-holes." It was on one of his jars of varnish the the year '93 was on the label, not on the ground bottle which was labeled "13B Medium Dark". Earlier in the chapter he had commented that he didnt use propolis anymore for the ground because it very slow drying and never gets really crisp. Also that linseed oil gets leathery and damps the vibration so it is not a good ground. I have the Sacconi book, but haven't spent much time with the varnish chapter.

Couple of other questions about grounds: if shellac were a component of the Cremonese ground, wouldn't it show up as a protein in chemical analysis? Secondly, the description of the Zygmundtovicz ground has him working it into the wood under a heat lamp with his bare hands and making a comment about ithe EPA not approving of such handling of a hazardous substance. IIRC, he was using enough heat that it was just starting to smoke. Further, he took it from a bottle that had a long ago date on it. Heat thinning suggests a low melting point resin or gum in alcohol or turpentine, hazardous suggests Gamboge. Any guesses what he uses to "glue the fibers together"? Thanks,

No clickers here. Anyone who has ever dealt with an Old English with diarrhea knows why we dock tails. All members of PETA should be required to do this for a week and a lot of their nonsense would go away

Great thread! Sharron: What breed? My wife has bred, shown and obedience trained Old English Sheepdogs for 28 years. Melvin: Tell us the story of the downfall of the Hills. I will eye that locomotive with suspicion if it presents a threat to my violin activity which for me is a greatly entertaining winter passtime until trout season comes around again.

My kind of having fun includes Fly Fishing http://www.amazon.com/Fly-Fishing-South-Pl...7932&sr=1-1 Audio Yup, I built a pair of these, 1100 Volt B+, kill you dead in one heartbeat if you screw-up. Metal Work, been working on this locomotive since I was a wee puppy, get back to it when I've finished a few violins. Also, R/C model airplanes, bicycling and whatever new wild-hair takes my fancy.

Hi Michael: What Sacconi says (page 29) is a bit more complicated even than that, and internally inconsistent: "B represents the center of gravity which divides the belly into two equal surfaces of equal weight and along which the inside notches of the ff-holes and the feet of the bridge are placed;" We have equal weight above and below the bridge line only with flat arching and uniform graduation and density. In the general case, equal weights above and below the line do not place the cg on the line. A fundamental misunderstanding by Sacconi. You are correct (as usual), plates do not balance at the bridge line without a extreme effort to make them do so.

Thanks, Michael. That will give me plenty to worry about on our first snowy day. FYI, I did work out the f-hole locations for a GdG inspired plate based upon pin separation distances as presented in the Strad article on Cremonese f-hole location for a GdG violin, even carved them into the plate. They end up being clearly wrong (2mm too far from edge, ...yeah, I know, cut first, measure later), though I will finish the violin with them that way anyway. Very interesting to the anally compulsive geometry freak.

Hi Michael: I've followed the construction of the Guarneri viola outline on Denis' site, and it is elegant. Did GdG start with some modified ratios? Could you comment on what is different in the Denis layout procedure that leads to the corners of a GdG being in slightly different locations from those of a Strad? For those who haven't seen this, find "Learning to Draw" at this site http://www.traitedelutherie.com/

this thread is beginning to touch on a lot of the ideas expressed by Jack Fry. Does he possibly know something about this? http://digicoll.library.wisc.edu/cgi-bin/w...&q2=&q3

A quick and dirty summary is that the radiated SPL is proportional to the velocity of the surface of the radiator, and inversely proportional to the square of the distance between the radiating surface and the measurement point, i.e. SPL~velocity/(distance)^2 Now, good old Newton gave us F=ma. The force moving the surface is closely described by a spring constant, F= -kx where k is a constant and x is the displacement of the surface from its neutral position, leading us to mass x acceleration = -kx or acceleration ~k/m A bigger k, i.e. stiffer spring gives us higher acceleration and subsequent higher peak velocities while a bigger mass gives a lower acceleration and subsequent lesser peak velocity. For higher radiated SPL you want stiffer wood and lower mass in some optimum combination. Maybe sitka is the optimum. Certainly carbon fiber will have a better ratio

Hi Bruce: The fundamental problem with cd's is that not all cd digital to analog conversions are created equal. Some of the D->A conversions (DAC) introduce a high frequency ringing. A sum of two sinusoids (i.e. the desired frequency plus the ring frequency) produces two other sinusoids which have frequencies of the sum and difference of the frequencies. The difference frequency may lie within the audible range and for some people, principally those with hearing like bats (such as my wife) the cd produced sound will be annoying or tiring. For many, such as myself, the sound of a non oversampling DAC will be preferable. Others like the added sizzle. Vinyl has none of these difficulties. "Your mileage may vary".......

I don't have the Denis book, but certainly appreciate what he has put on his website under "Learning to draw." Watching the animation, one decides the desired length of the body, divides by the golden ratio, draws a square of that dimension and with a few more strokes of the compass and straight edge, the four corner locations are defined. Now, what did del Gesu do differently that resulted in a lower location for the lower corners on his violins? Hope this isn't too far off topic. Thanks

all I get by clicking the link is a black screen. have downloaded and reinstalled JAVA. Have real player. How do you make it run? What does it show? Thanks

Hi David: Do you still have these notes? If so, can copies be made available or posted? Thanks, Roger Hill

If the overtone structure is varying, over what sort of time intervals? Something on the order of a vibrato frequency (fifth of a second, say) Hi John: Doesn't the ordinary waterfall plot contain this information?

I KNEW he would be lying under a catenary. In fact, I will bet five gallons of fresh pee that it was the catenary of an inhomogeneous chain.............

When we get to the bottom line, we are stuck with the differences between making measurements on physical systems, versus those of making measurements on biological systems. If we send 100 competent physicists into the lab to measure the specific heat of water, they will all get the same answer to within a few percent. If we ask them to measure the sound output transfer function of a violin, they again will all get the same answer. If we ask them to measure "which violin sounds the best", there will be no answer because the question is not well posed.......there will be no agreement as to what "best" means and thus, the question is meaningless. All we are left with is the subjective agreement of what the players think. The simple fact is that the biological system for deciding "best" is too complex to allow results to be expressed in numbers.

Please do call at any time. I love to talk stereo, violins, fly fishing, music, etc. ..........we'll have to go fishing for more serious conversations As to food, I only serve steak from dead steers which can no longer move about .........

GMM22: I think that you did not notice tongue firmly implanted in cheek. Everyone else (and GMM22): If your vacation plans take you through Colorado Springs, you are invited to stop in for a great steak, good wine and enough A-B comparisons of stereo equipment to glaze over your eyes and boggle your ears. Bring all the CD's/LP's you wish to compare to your home equipment or you will have to listen to all of my preferred tracks. Phone is (719) 593-5927. Need about a days notice unless I'm in Montana fishing. OK, Bill: I hear wax or disc or wire noise and confuse it for what sounds like tape hiss. Noise is noise.......and the emotion Caruso conveys is still amazing. Never mind the noise, that dude could sing opera.