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Free Plate Tuning, Part Two: Violins

Free Plate Tuning, Part Two: Violins

by Alan Carruth

Originally published in American Lutherie #29, 1992 and Big Red Book of American Lutherie Volume Three, 2004

See also,
Free Plate Tuning, Part One: Theory by Alan Carruth
Free Plate Tuning, Part Three: Guitars by Alan Carruth



Before I get into plate tuning proper I’d like to digress a bit and discuss the rationale behind the process, and a couple of other things I find it useful to keep in mind while I’m working. And I can’t think of a better way to begin than by telling you about one of my more elaborate experiments.

Fig. 15 gives the relevant information on my fourth and fifth violins. The idea was to check out the influence of asymmetric back graduations by building a pair of closely-matched fiddles with that as the only variable. The one-piece backs were cut from the same plank of bird’s-eye maple and the tops were cut from a red spruce 4×6 that I took out of the wall of my house when I put in a new chimney. The molds were routed using a template. Archings were checked for height at over two dozen points on each plate and were held to .2MM. Graduation, weight, and frequency data is as shown. The delta f mentioned is the frequency drop obtained when a 5G weight was stuck to the plate in an active area of the given mode. Fittings and so on were matched as closely as possible, and the two bridges were cut back to back from the same piece of maple.

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Letter: Beam Stiffness vs. Strength

Letter: Beam Stiffness vs. Strength

by Fred T. Dickens

Originally published in American Lutherie #41, 1994



Dear Sir,

Please allow me to attempt a termination of the continuing misunderstandings originating with Mr. Ervin Somogyi’s interesting but flawed lecture given at the ’92 conference in South Dakota and perpetuated by its subsequent transcription in the GAL Journal and the letter in American Lutherie #39 from Mr. Dave Schwab commenting on the matter.

The issue has to do with using the terms “strength” and “stiffness” interchangeably when discussing the mechanical characteristics of beams used as braces in guitar sounding boards.

Both strength and stiffness of beams are important characteristics and depend on properties of the materials from which the beams are constructed as well as the physical dimensions of the beam. Both stiffness and strength of beams may be calculated using formulas which only require a knowledge of the material properties and physical dimensions. Those so inclined will find a very readable account of these formulas in Understanding Wood by R. Bruce Hoadley, ISBN 0-918804-05-01.

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Free Plate Tuning, Part Three: Guitars

Free Plate Tuning, Part Three: Guitars

by Alan Carruth

Originally published in American Lutherie #30, 1992 and Big Red Book of American Lutherie Volume Three, 2004

See also,
Free Plate Tuning, Part One: Theory by Alan Carruth
Free Plate Tuning, Part Two: Violins by Alan Carruth



The guitar is somewhat simpler acoustically than the violin, and perhaps more limited. As a result it has evolved into a number of more or less specialized forms to suit different musical uses. It is difficult to imagine a guitar that could “do it all” the way a good violin can. Rather, each guitar seems to have a “center,” a sound that is characteristic of it that suits it for a particular style or player. Good guitars do have a wide dynamic and timbral range, but they always retain their characteristic sound.

As I see it, a good part of the art in this game is deciding where you want the “center” to be, or, alternatively, how to get the “center” you want out of a given shape or set of wood. And then you want to have a broad dynamic and expressive range, good balance, and clarity or resolution; the ability to distinguish things like inner lines. No amount of acoustic science is going to tell you what priority to put on the different characteristics of the sound, nor whether you have succeeded in the end. But if you know what you’re doing, an oscillator and a jar of glitter can help you get the sound you want.

One of the main simplifying factors between the guitar and the violin is the lack of a soundpost in the guitar. This allows the top and the back to be more independent; in acoustic terms they are not so tightly coupled and can act out of phase.

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Dissolving the Mysteries

Dissolving the Mysteries

by Graham Caldersmith

previously published in Guild of American Luthiers Quarterly Volume 10, #4, 1982 and Big Red Book of American Lutherie Volume One, 2001



We live in confusing times where progress in understanding the natural world, and in manipulating nature to our advantage has spawned an ever-changing technological environment that seems beyond our own control, and even beyond our comprehension in its scale and complexity. We are beginning to see organized reaction against technological excess, and movements towards simpler ways of living. Most luthiers are aware that the practical and traditional practice of lutherie is being analyzed and even supplemented by scientific methods, and some feel that the dignity and integrity of the traditions are therefore threatened as we redefine and dissolve the mysteries of lutherie.

I would argue that the greatest system of lutherie to date, the Renaissance-Baroque school of violin making emerged in times of devastating plague and recurring war, when the orthodoxy of creation and nature was being challenged by Galileo and Copernicus in centers not far from Brescia, Cremona, and southern Germany. In fact we know that because the centers of Baroque violin making lay on the trade routes through which the latest news in science, art, and technology flowed with trade merchandise. The great masters of lutherie would have been exposed to new concepts in vibration, pitch, and wave motion which they would find difficult to ignore in their experience of wood vibration at the workbench. How they dealt with it is not recorded, but that they produced unsurpassed masterpieces in bowed instruments is undisputed.

Contemporary luthiers live in times of social upheaval, war, and pollution, but also with a growing body of knowledge about the function of the instruments they make. It remains to be seen how we will react to this environment, but already we have seen a variety of new designs for the guitar, and the vital interaction of luthiers with pioneering guitarists.

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Controlling Strings, Wood, and Air

Controlling Strings, Wood, and Air

from her 1979 GAL Convention lecture

Originally published in Guild of American Luthiers Quarterly Volume 8, #3, 1980 and Big Red Book of American Lutherie, Volume 1, 2000



I’d like to take a minute to tell you a story. Imagine the scent in front of a cave some 20,000 years ago. A family has just killed a bear and is skinning it and preparing the meat for food. They’ve given some of the rawhide to their young son who has made some strips to string his first hunting bow. He and his sister are sitting out in front of the cave trying to tie some of the slippery strips to the bow-stick. As they do this the boy puts one end of the stick in his mouth to hold it steady as he tightens and ties the slippery stuff. As he plucks the rawhide to check the pull he suddenly realizes he can get different sounds depending on how he bites the stick and shapes his lips and cheeks around it.

This could have been the origin of the musical bow. When I told this story in Ames, Iowa, a few years ago it created quite a lot of interest. After the lecture they produced a record of someone playing the mouth bow. I now have a mouth bow that a young man made for me which is quite a challenge to try to play.

Actually, we are working with the same three elements that the young cave boy had under his control: strings, wood, and air. He could vary all three of these quite easily to a certain extent. In our modern bowed and plucked strings, however, the wood and the air resonances are more or less set when the instruments are made. For years I have worked to test the effects of variations in the wood and air resonances, but it means taking the instruments apart to thin the plates or slice down the height of the ribs (on expendable instruments, of course!)

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