Guitar bracing refers to the system of wooden struts which internally support and reinforce the soundboard and back of acoustic guitars.
Soundboard or top bracing transmits the forces exerted by the strings from the bridge to the rim. The luthier faces the challenge of bracing the instrument to withstand the stress applied by the strings with minimal distortion, while permitting the top to respond as fully as possible to the tones generated by the strings. Brace design contributes significantly to the type of sound a guitar will produce. According to luthiers W. Cumpiano and J. Natelson, "By varying brace design, each builder has sought to produce a sound that conformed to his concept of the ideal." [1]
The back of the instrument is braced to help distribute the force exerted by the neck on the body, and to maintain the tonal responsiveness and structural integrity of the sound box.
Braces may be made from top woods (spruce or cedar), balsa wood or, in high-end instruments, carbon fiber composites.
This is the standard bracing pattern on the classical guitar, dating to the work of Antonio Torres Jurado in the 19th century. Although the originator of this bracing style has not been reliably established, the earliest known use is by Spanish luthier Francisco Sanguino in the mid to late 18th century. [2]
In the 1970s, scientist Michael Kasha radically overhauled every aspect of guitar design to incorporate principles such as mechanical impedance matching. [3]
The Australian guitarmaker Greg Smallman introduced guitars with an extremely thin soundboard, which is supported by bracing in the shape of a lattice. Smallman combines this with heavier, laminated back and sides with a frame. Smallman's guitars are used by John Williams.
Smallman's design was inspired by research by Torres who made a guitar with a papier mâché back and sides to show that the soundboard was the most important factor in guitar sound projection. Smallman also uses two 45 degree pole supports in the frame running from the bottom of the guitar to the waist to prevent the string tension from distorting the body and sound board.
In all steel-string instruments, the ends of the top braces taper at the edge of the soundboard. In most factory built guitars the brace tops are given a round profile, but are otherwise left unshaped. This produces a stronger top and may reduce the number of warranty claims arising from damage, however, over-built tops are less responsive. [4] Braces are usually made from Sitka Spruce (Picea sitchensis). [5] Some luthiers use Adirondack Spruce, also known as "Red Spruce" (Picea rubens), in high end instruments.
The tops of most steel string acoustic guitars are braced using the X-brace [6] system, or a variation of the X-brace system, generally attributed to Christian Frederick Martin between 1840 and 1845 for use in gut string guitars. [7] [8] The system consists of two braces forming an "X" shape across the soundboard below the top of the sound hole. The lower arms of the "X" straddle and support the ends of the bridge. Under the bridge is a hardwood bridge plate which prevents the ball end of the strings from damaging the underside of the soundboard. Below the bridge patch are one or more tone bars which support the bottom of the soundboard. These abut one of the X braces and usually slant down towards the bottom edge of the soundboard. The top tone bar butts against a portion of the bridge patch in most instruments. Above the sound hole a large transverse brace spans the width of the upper bout of the soundboard. Around the lower bout, small finger braces support the area between the X-braces and the edge of the soundboard.
In this system, two overlapping X shapes form a diamond surrounding the underside of the bridge plate. Some luthiers prefer it where additional strength is required, for instance for twelve string guitars. This bracing does not allow the top to move or vibrate as much as it normally would but offers more strength and prevent bellying around the bridge area.
Several bracing styles are designated as A-bracing. Mottola's Cyclopedic Dictionary of Lutherie Terms [9] lists two. The first, typical of instruments built by Tacoma, use two long longitudinal struts that diverge from near the neck block to near the tail end of the guitar. This bracing style is used on instruments that feature a soundhole that is not centrally located. The second style listed is that used by some models of Ovation guitars, also called Adamas bracing. There is also a variation on X-bracing called A-bracing. The X-shaped structure under the bridge is retained, but the transverse strut between the fingerboard and soundhole is replaced by two diagonal braces which splay outward going toward the soundhole. It is used by Lowden Guitars.
V-Class bracing is a bracing style developed by Andy Powers for Taylor Guitars. It is similar to A-bracing, however the main braces diverge across both sides of the sound hole towards the neck side of the top, and converge at the endblock to form the shape of a V. A lateral brace positioned between the soundhole and bridge plate spans the width of the top, and there are two sets of tone/finger braces between the bridge plate and endblock that are roughly perpendicular to the longitudinal V-braces and run from the V-brace towards the edge of the top. It is purported to allow the top to be both stiff and flexible in order to produce more volume and sustain. Taylor also purports that the design improves harmonic intonation. [10]
Falcate (sickle-shaped) bracing is a symmetric bracing style designed by luthier and engineer Trevor Gore, and used on his steel-string and classical nylon-string guitars. It claims a more even sound over the frequency spectrum, and more responsiveness and volume without being too delicate.
Luthiers building higher quality instruments adjust the stiffness of the top and shape the braces to maximize the response of the top while maintaining structural integrity. Tone bars and bottom halves of the X-braces may be either scalloped or parabolic in shape. Above the X-brace joint, braces usually have a parabolic shape. Experienced luthiers 'voice' or 'tap-tune' the tops and backs of high end guitars to produce optimum tone and responsiveness in the hands of the player. [11]
Bracing style and shape will affect the tone of the instrument. According to luthiers Bob Connor and David Mainwaring, "scalloped braces will produce a warmer sounding bass response in the guitar with smooth mids and crisp highs. Parabolic braces will yield a quick response with a more pronounced mid range and a more focused bottom end." [12]
This simple system, where braces are arranged parallel to each other and perpendicular to the direction of the strings, is employed on most guitar backs. The earliest steel string guitars very often had ladder braced tops, a practice which survives in the Maccaferri guitar. It is considered more suitable for parlor guitars and lightly strung instruments. [13]
Archtop guitars originally had two near-horizontal braces or "tone bars" on either side from bridge to neck, a system known as parallel bracing. The braces roughly run under the feet of the archtop guitar's bridge. X-bracing, similar to that of flat-top guitars was later introduced. Their tops are inherently stronger than flat tops, so less bracing may be required. "Trestle" bracing was a system used on some Gretsch archtops [14]
The steel-string acoustic guitar is a modern form of guitar that descends from the gut-strung Romantic guitar, but is strung with steel strings for a brighter, louder sound. Like the modern classical guitar, it is often referred to simply as an acoustic guitar, or sometimes as a folk guitar.
The guitar is a stringed musical instrument that is usually fretted and typically has six or twelve strings. It is usually held flat against the player's body and played by strumming or plucking the strings with the dominant hand, while simultaneously pressing selected strings against frets with the fingers of the opposite hand. A guitar pick may also be used to strike the strings. The sound of the guitar is projected either acoustically, by means of a resonant hollow chamber on the guitar, or amplified by an electronic pickup and an amplifier.
A mandolin is a stringed musical instrument in the lute family and is generally plucked with a pick. It most commonly has four courses of doubled strings tuned in unison, thus giving a total of eight strings. A variety of string types are used, with steel strings being the most common and usually the least expensive. The courses are typically tuned in an interval of perfect fifths, with the same tuning as a violin. Also, like the violin, it is the soprano member of a family that includes the mandola, octave mandolin, mandocello and mandobass.
C.F. Martin & Company is an American guitar manufacturer established in 1833 by Christian Frederick Martin. It is highly respected for its acoustic guitars and is a leading manufacturer of flat top guitars and ukuleles. The company has also made mandolins and tiples, as well as several models of electric guitars and electric basses, although none of these other instruments are still in production.
A fret is any of the thin strips of material, usually metal wire, inserted laterally at specific positions along the neck or fretboard of a stringed instrument. Frets usually extend across the full width of the neck. On some historical instruments and non-European instruments, frets are made of pieces of string tied around the neck.
The fingerboard is an important component of most stringed instruments. It is a thin, long strip of material, usually wood, that is laminated to the front of the neck of an instrument. The strings run over the fingerboard, between the nut and bridge. To play the instrument, a musician presses strings down to the fingerboard to change the vibrating length, changing the pitch. This is called stopping the strings. Depending on the instrument and the style of music, the musician may pluck, strum or bow one or more strings with the hand that is not fretting the notes. On some instruments, notes can be sounded by the fretting hand alone, such as with hammer ons, an electric guitar technique.
A luthier is a craftsperson who builds or repairs string instruments.
An archtop guitar is a hollow acoustic or semi-acoustic guitar with a full body and a distinctive arched top, whose sound is particularly popular with jazz, blues, and rockabilly players.
The Selmer guitar — often called a Selmer-Maccaferri or just Maccaferri by English speakers, as early British advertising stressed the designer rather than manufacturer — is an unusual acoustic guitar best known as the favored instrument of Django Reinhardt. Selmer, a French manufacturer, produced the instrument from 1932 to about 1952.
The Ovation Guitar Company is a manufacturer of string instruments. Ovation primarily manufactures steel-string acoustic guitars and nylon-string guitars, often with pickups for electric amplification. In 2015, it became a subsidiary of Drum Workshop after being acquired from KMCMusicorp.
A multi-scale fingerboard is an instrument fretboard which incorporates multiple scale lengths. This allows each of the strings to have a different string tension and thus, balanced tonal characteristics.
The octave mandolin or octave mandola is a fretted string instrument with four pairs of strings tuned in fifths, G−D−A−E. It is larger than the mandola, but smaller than the mandocello and its construction is similar to other instruments in the mandolin family. Usually the courses are all unison pairs but the lower two may sometimes be strung as octave pairs with the higher-pitched octave string on top so that it is hit before the thicker lower-pitched string. Alternate tunings of G−D−A−D and A−D−A−D are often employed by Celtic musicians.
A person who is specialized in the making of stringed instruments such as guitars, lutes and violins is called a luthier.
An acoustic guitar is a musical instrument in the string family. When a string is plucked, its vibration is transmitted from the bridge, resonating throughout the top of the guitar. It is also transmitted to the side and back of the instrument, resonating through the air in the body, and producing sound from the sound hole. While the original, general term for this stringed instrument is guitar, the retronym 'acoustic guitar' – often used to indicate the steel stringed model – distinguishes it from an electric guitar, which relies on electronic amplification. Typically, a guitar's body is a sound box, of which the top side serves as a sound board that enhances the vibration sounds of the strings. In standard tuning the guitar's six strings are tuned (low to high) E2 A2 D3 G3 B3 E4.
Tonewood refers to specific wood varieties used for woodwind or acoustic stringed instruments. The word implies that certain species exhibit qualities that enhance acoustic properties of the instruments, but other properties of the wood such as aesthetics and availability have always been considered in the selection of wood for musical instruments. According to Mottola's Cyclopedic Dictionary of Lutherie Terms, tonewood is:
Wood that is used to make stringed musical instruments. The term is often used to indicate wood species that are suitable for stringed musical instruments and, by exclusion, those that are not. But the list of species generally considered to be tonewoods changes constantly and has changed constantly throughout history.
Tacoma Guitars was an American manufacturing company of musical instruments. It was founded in 1991 as a division of South Korean company Young Chang. Instruments were manufactured in Tacoma, Washington. The company and brand name were later acquired by the Fender Musical Instruments Corporation. The Tacoma plant closed, and production ceased, in 2008.
William Richard Cumpiano is a builder of stringed musical instruments and is known for his writing and teaching of the art of luthiery. He has been involved in the preservation and understanding of the fading musical and musical craft traditions of his native Puerto Rico. Cumpiano was instrumental in the development of the first feature-length documentary about the cuatro and its music, Our Cuatro: The Puerto Ricans and Stringed Instruments, Volumes 1 and 2.
The dreadnought is a type of acoustic guitar body developed by American guitar manufacturer C.F. Martin & Company. The style, since copied by other guitar manufacturers, has become one of the most common for acoustic guitars. Its shape is characterized by square shoulders, a relatively flat tail end, and a wide waist with a large radius curve.
A bridge is a device that supports the strings on a stringed musical instrument and transmits the vibration of those strings to another structural component of the instrument—typically a soundboard, such as the top of a guitar or violin—which transfers the sound to the surrounding air. Depending on the instrument, the bridge may be made of carved wood, metal or other materials. The bridge supports the strings and holds them over the body of the instrument under tension.
Jeffrey Yong is a Malaysian luthier noted for using local Malaysian wood in his instruments and for his innovative designs. Yong has exhibited at conventions in the United States, Canada, Japan, Russia and China. He founded the Guitar Institute of Malaysia.