Posted on March 4, 2022May 21, 2025 by Dale Phillips Thoughts on Soundboard Vibration Thoughts on Soundboard Vibration by Paul Wyszkowski Originally published as Guild of American Luthiers Data Sheet #200, 1981 The classic guitar, like the harp but unlike the violin, the mandolin or the zither, has its strings attached directly to the soundboard. In the case of a violin, it is pretty clear that the bridge communicates primarily vibrations which are perpendicular to the surface of the soundboard. But it is not so obvious how the strings of a guitar transmit their vibration to the soundboard. However, a few minutes’ thought and a simple experiment can settle that question. Back in 1954, J.K. Sutcliffe stated in an article in Guitar News that the fundamental action linking the string to the soundboard is the rocking of the bridge in response to the longitudinal (along the length) vibrations of the string. That is, the front and back edges of the bridge rise and fall as the string becomes tighter and looser (see Fig. 1). Later, Michael Kasha used this idea in his theory of guitar design. As a consequence, this view was accepted by many luthiers as correct. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.
Posted on October 25, 2021May 14, 2025 by Dale Phillips Geometric Design of the Stradivari Model G Violin, Part One: Mold and Template Geometric Design of the Stradivari Model G Violin, Part One: Mold and Template by Robert J. Spear Originally published in American Lutherie #93, 2008 see also, Geometric Design of the Stradivari Model G Violin, Part Two: f-holes by Robert J. Spear Geometric Design of the Stradivari Model G Violin, Part Three: The Scroll by Robert J. Spear I have little doubt that artists, artisans, and architects of the Renaissance and Baroque used some system of guidance for their drawings that was based on the knowledge of geometry and the use of straightedge and divider. I began my drawing adventure almost five years ago by following the guidelines for the geometric design of the Model G in Sacconi’s book and soon discovered errors. Even so, I was convinced that it would be worthwhile to use a classical Cremonese approach based on geometry because I wanted to see if I could integrate it with Hutchins and Schelleng’s scaling theories used for the New Violin Family. While the acoustical aspects of the exercise are not germane here, I worked to realize a design system that would essentially produce a second generation of octet instruments close to a classical Cremonese violin in the style of the Model G Stradivari. My goal was to impart a greater uniformity to the octet family’s models, but to keep this article within bounds I have confined my remarks to the violin. There are those who question whether geometric design really played an important role in violin design and suggest that the model outline could be designed freehand. Others allow that some sort of geometrical or proportion scheme was used, but that it was not based on the golden section. A few ask why one can’t just get a good photo of a good model and enlarge or reduce it at the local copy center. You can (and I did at first), but because strange things start to happen in the larger and smaller instruments during the scaling process, straight scaling does not hold up. Still others, including Sacconi, stress that the eye was the final arbiter of any design, no matter how it was derived. I will attempt to address all of these points in this series of articles. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.
Posted on October 25, 2021May 14, 2025 by Dale Phillips Geometric Design of the Stradivari Model G Violin, Part Two: f-Holes Geometric Design of the Stradivari Model G Violin, Part Two: f-Holes with Robert J. Spear Originally published in American Lutherie #94, 2008 see also, Geometric Design of the Stradivari Model G Violin, Part One: Mold and Template by Robert J. Spear Geometric Design of the Stradivari Model G Violin, Part Three: The Scroll by Robert J. Spear The Cremonese design for the f-holes of a violin, at first glance, would appear to be based on the same design philosophy as the body and to make extensive use of the golden section. A. Thomas King, in his article “The Cremonese System for Positioning the f-Holes” in The Strad, shows rather convincingly that golden-section divisions based on the distance between the pins on the body was employed to fix the location of the f-hole eyes, which further reinforces this idea. However, when it comes to f-holes, I would like to suggest that there are a couple of additional jokers in the deck. First, the late Cremonese f-hole is derived from an earlier system of design, and some of the important parts of the predecessor system remain in use; second, an entirely different modulus is used for the f-holes than for the body; and, third, little is based on the golden section. The Forma G violin, upon which my model is based, is not quite the longest violin Stradivari ever made, but it is the widest. The most notable increase in width is in the center bout, which has another direct impact on the design of the f-hole and its placement. King notes that there is a general method for most Cremonese violins and a specialized adaptation for Stradivari violins. King explained the rather unintuitive step of taking the golden section of the distance between the locating pins in the top as the modulus for positioning the f-holes. I have used his approach here because it has many good points of correlation, and because I found an additional correlation that has convinced me even further that his hypothesis is correct. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.
Posted on August 11, 2021May 14, 2025 by Dale Phillips Violin Ribs/Latent Tension Violin Ribs/Latent Tension by John Meng Originally published in Guild of American Luthiers Data Sheet #287, 1984 and Big Red Book of American Lutherie Volume One, 2000 Bending Ribs When wood is bent, the length of the outer surface increases or the length of the inner surface decreases; or most likely some combination of the two occurs. In soft woods, the fibers stretch and compress more easily than they do in hard woods, so soft woods can successfully be bent to smaller radii than can hard woods before the wood fractures. Thin maple strips used to form violin ribs must be bent to small radii at the corners. Maple being a hard wood, there is a tendency for fibers along the inner surface to strongly resist compression. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.
Posted on June 23, 2021May 19, 2025 by Dale Phillips Finite Element Simulation of Guitar Top Vibration Finite Element Simulation of Guitar Top Vibration by Phil Banks Originally published in American Lutherie #18, 1989 The use of engineering finite element analysis software to determine modes and natural resonant frequencies of a guitar top can be a useful (albeit lengthy) process which, if used judiciously, can yield useful information to the guitar maker. As a graduate mechanical engineer and a guitar maker, I’ve always been interested in marrying the discipline of the luthier’s craft with that of science. I got that chance last year at the University of Sydney. While working as a programmer developing a Finite Element package, I was asked to produce a demonstration of the program’s capabilities. I decided to analyze a guitar top. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.
