Posted on April 12, 2021May 16, 2025 by Dale Phillips Free Plate Tuning, Part One: Theory Free Plate Tuning, Part One: Theory by Alan Carruth Originally published in American Lutherie #28, 1991 and Big Red Book of American Lutherie Volume 3, 2004 See also, Free Plate Tuning, Part Two: Violins by Alan Carruth Free Plate Tuning, Part Three: Guitars by Alan Carruth I started learning free plate tuning on violins and violas more than ten years ago from Carleen Hutchins. For those who have not had the pleasure of her acquaintance, Carleen is one of the founders of the Catgut Acoustical Society and its permanent secretary. She is an able scientist, a great teacher, a fine luthier, and a self-confessed mediocre violist. While working with physicist Frederick Saunders almost thirty years ago she helped rediscover and update the old Chladni method of visualizing the vibrations of plates. Her subsequent research, using Chladni patterns as a window into the differences between good and poor violins earned her a silver medal from the Acoustical Society of America. Violin makers have traditionally used some variant of “tap tone” tuning to guide them in working out the final graduations of the top and back plates. Although the technique seems simple and organic on the face of it, it is in fact very complex. It takes a long time, as well as a good ear and a lot of talent, to learn to tune plates by tap tone. Even those who are good at it don’t always succeed. Felix Savart, back in the 19th century, tried to adapt Chladni’s method to research on violin acoustics, but the technology wasn’t there. Now we have the means, and as we gain more understanding of how the instruments work, we also gain more control over the sound. And it doesn’t only work on violins. Fred Dickens, Graham Caldersmith, and Gila Eban have all done major work in applying the principles of violin acoustics to guitar construction. Of course, there are differences and it takes time and effort to sort them out, but physics is physics, or, as a friend of mine said, “it all comes down to F=mA in the end.” I have found these techniques to be useful, and sharing useful techniques is what the Guild is all about. 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 April 7, 2021May 16, 2025 by Dale Phillips In Search of the Perfect Cone In Search of the Perfect Cone by Tim Earls Originally published in American Lutherie #30, 1991 and Big Red Book of American Lutherie Volume Three, 2004 I think I've got it. I have here an untested method of finding the exact, correct multiple radius for any given fingerboard using simple barnyard geometry and no computer. Danny Rauen and Tim Olsen wrote interesting articles on multiradiused, or conical, fretboards in American Lutherie #8. (See Big Red Book of American Lutherie Volume One, p. 298.) Great stuff! Let’s talk about cones for a moment. A cone is a tapered cylinder extended up to a point. Or a tapered cylinder is a cone with its point lopped off, take your pick. You knew that. Bear with me. In a two-dimensional view, this looks like Fig. 1. The circular base of the cone is seen as a horizontal line, since you’re looking at its edge. The height of the cone, what I call “true length” is measured on the centerline from base to point. The side line of the cone I call “true distance.” The radius at any spot on this cone can be found by drawing a horizontal line from the centerline to the true distance line and measuring it. You probably knew that too. 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 17, 2020May 21, 2025 by Dale Phillips Basics of Air Resonances Basics of Air Resonances by W.D. Allen Originally published in American Lutherie #1, 1985 and Big Red Book of American Lutherie Volume One, 2000 Stringed musical instruments with soundboxes typical of the guitar and violin families have many internal air resonances. The resonance with the lowest frequency is called the Helmholtz resonance, and its importance to the quality of the instrument is appreciated. The resonances with higher frequencies have been referred to by different names: higher Helmholtz, cavity modes, or standing wave modes. These resonances have been measured and documented for several different instruments, but there seems to be little information on their controlling parameters. The intent of this article is to give the instrument builder some understanding of the air resonances, what parameters establish the frequencies, and some insight into the potential for using this information to make better instruments. A minimum-math, pictorial approach with approximation and rounded-off numbers will be used. Showing the effects of the controlling parameters is the objective, not the absolute value of a number. 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 May 4, 2020May 16, 2025 by Dale Phillips 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. 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 March 2, 2020May 16, 2025 by Dale Phillips 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. 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.
