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Improved X Bracing

Improved X Bracing

by Don Musser

Originally published as Guild of American Luthiers Data Sheet #172, 1981 and in Lutherie Woods and Steel String Guitars, 1997



After building a number of guitars with the standard steel string X-bracing pattern, I noticed some problems. First, even when the braces were precurved to a 25' radius, there was still a deformation just behind the bridge that was caused by the upward pull of the strings on the inner bridge plate. Energy which could have gone to sound production in the whole top was being lost to wood deformation in a small area of the top.

Second, there was always a problem of creating a guitar having both an outstanding bass and treble response. Good bass response requires less or lighter bracing on the bass side of the top. A crisp, well-defined treble requires more or slightly heavier bracing on the treble side. The challenge was to be able to achieve both without retarding either.

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The Bluegrass Dobro

The Bluegrass Dobro

America’s Second Native Instrument

by Bobby Wolfe

Originally published in American Lutherie #5, 1986 and Big Red Book of American Lutherie, Volume One, 2000



There is a little ditty known as “The Duck Principle.” It says: If it looks like a duck, if it walks like a duck, if it quacks like a duck, then it must be a duck. Well, since the Dobro only looks like a guitar, and even in this respect with significant differences, and doesn’t qualify in the other ways, I say it’s not a duck.

Seriously, in my opinion, the mechanically amplified instrument known as the Dobro does qualify as America’s second native instrument.

This article is designed to acquaint you with the Dobro and to provide information on common repair and setup needs of the instrument. Today, in addition to the members of The Original Family building the original instrument, there are many individuals building their versions. Most of these people have their own ideas and opinions about what works best. Therefore, I am not presenting my ideas, experiences, and working practices as the “last word.”

First, let’s define Dobro. It is a registered brand name that is now also used generically to describe most resonator-type guitars. The name comes from the Dopera (Dopyera) brothers. There are five Dopera brothers. There are five letters in Dobro. The word dobro means “good” in their native Slavic language. Take your pick!

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Commercial Graphite Acoustic Guitars

Commercial Graphite Acoustic Guitars

by John A. Decker, Jr.

Originally published in American Lutherie #31, 1992 and Big Red Book of American Lutherie, Volume Three, 2004



Why would anyone want to build an acoustic guitar of graphite? The primary reason is that wooden acoustic guitars (particularly good ones) are fragile. They are especially prone to cracking, warping, and joint separation due to heat, humidity, and water. Graphite/epoxy technology — properly employed, which isn’t easy — can maintain the sound quality of a wooden guitar while completely removing its susceptibility to heat and moisture.

During the past seven years Kuau Technology has been working with luthiers at the firm of Pimentel & Sons, of Albuquerque, New Mexico, in the development of acoustic guitar technology employing fiber-reinforced resins, particularly graphite/epoxy. Our approach has been to duplicate as closely as possible, panel by panel, the acoustic properties of fine wooden classical guitars, rather than attempt to reinvent the guitar de nova. This work has resulted in the development of the RainSong® Graphite Acoustic Guitars,* which we believe to be the first commercially available all-graphite acoustic guitars.

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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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Intonation in the Real World

Intonation in the Real World

by Mike Doolin

from his 2006 GAL Convention lecture

previously published in American Lutherie #92, 2007



Getting guitars to play in tune has been a major topic of interest for many years, both for guitar players and guitar makers, and it has been a major source of frustration as well. During our current “Golden Age of Lutherie” the bar has been raised for standards of craft, playability, and tonal quality, as players have become more sophisticated in their expectations and builders have become better educated and more demanding of their own work. Expectations for accurate intonation have come along with all that: it’s no longer acceptable for a guitar to only play in tune for the first five frets, or in a few keys. Modern players are using the whole neck, exploring extended harmonies, and playing in ensembles with other instruments. They are looking for instruments that play in tune with themselves and with the rest of the musical world.

It turns out that guitar intonation is a huge can of worms, because it is really two topics:

▶ What does it mean to be “in tune?”
▶ How do I make a guitar do that?

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