crazy-guitar
2007/11/20
Guitar accessories
2007/11/19
Tuning
A variety of different tunings are used. The most common by far, known as "Standard Tuning" (EAdgbe'), is as follows (Helmholtz pitch notation):
- sixth (lowest tone) string: low E (a minor thirteenth below middle C—82.4 Hz)
- fifth string: A (a minor tenth below middle C—110 Hz)
- fourth string: d (a minor seventh below middle C—146.8 Hz)
- third string: g (a perfect fourth below middle C—196.0 Hz) - second string: b (a minor second below middle C—246.92 Hz)
- first (highest tone) string: e' (a major third above middle C—329.6 Hz)
The diagram above depicts pitch names found over the six strings of a guitar in standard tuning, from the nut (zero) to the twelfth fret.
A guitar using this tuning can tune to itself using the fact, with a single exception, that the 5th fret on one string is the same note as the next open string; that is, a 5th-fret note on the sixth string is the same note as the open fifth string. The exception is the interval between the second and third strings, in which the 4th-fret note on the third string is equivalent to the open second string.
Standard tuning has evolved to provide a good compromise between simple fingering for many chords and the ability to play common scales with minimal left hand movement. There are also a variety of commonly used alternate tunings - most of which are chord voicings that can be played on open strings or made by moving the capo. Alternate tunings are used for two main reasons: the ease of playing and the variation in tone that can be achieved.
Many guitarists use a long established, centuries-old tuning variation where the lowest string is 'dropped' two semi-tones down. Known as Drop-D (or dropped D) tuning it is, from low to high, DAdgbe'. This allows for open string tonic and dominant basses in the keys of D and D minor. It also enables simple fifths (powerchords) to be easily played without the need for a high technical skill level. Eddie Van Halen sometimes uses a device known as a 'D Tuna,' the patent for which he owns. It is a small lever, attached to the fine tuner of the 6th string on a Floyd Rose tremolo, which allows him to easily drop that string's tuning to a D. Many contemporary rock bands downtune the entire tuning by several semi-tones, making, for example, Drop-C or Drop-B tunings, However this terminology is inconsistent with that of "drop-D" as "drop-D" refers to dropping a single string to the named pitch. Often these new tunings are also simply referred to as the "Standard" of the note in question e.g. - "D Standard" (DGcfad'). Many other open tunings, where all of the strings are tuned to a similar note or chord, are popular for slide guitar playing.
As with all stringed instruments a large number of scordatura are possible on the guitar. A common form of scordatura involves tuning the 2nd string to Bb to mimic the standard tuning of the lute, especially when playing renaissance repertoire originally written for the lute.
Guitar construction and components
Frets are laid out to a mathematical ratio that results in equal tempered division of the octave. The ratio of the spacing of two consecutive frets is the twelfth root of two , whose numeric value is about 1.059463. The twelfth fret divides the scale length in two exact halves and the 24th fret position divides the scale length in half yet again. Every twelve frets represents one octave. In practise, luthiers determine fret positions using the constant 17.817, which is derived from the twelfth root of two. The scale length divided by this value yields the distance from the nut to the first fret. That distance is subtracted from the scale length and the result is divided in two sections by the constant to yield the distance from the first fret to the second fret. Positions for the remainder of the frets are calculated in like manner.[12]
Inlays
Fretboard inlays are most commonly shaped like dots, diamond shapes, parallelograms, or large blocks in between the frets. Dots are usually inlaid into the upper edge of the fretboard in the same positions, small enough to be visible only to the player. Some older or high-end instruments have inlays made of mother of pearl, abalone, ivory, coloured wood or other exotic materials and designs. Simpler inlays are often made of plastic or painted. High-end classical guitars seldom have fretboard inlays as a well trained player is expected to know his or her way around the instrument.
In addition to fretboard inlay, the headstock and soundhole surround are also frequently inlaid. The manufacturer's logo or a small design is often inlaid into the headstock. Rosette designs vary from simple concentric circles to delicate fretwork mimicking the historic rosette of lutes. Bindings that edge the finger and sound boards are sometimes inlaid. Some instruments have a filler strip running down the length and behind the neck, used for strength and/or to fill the cavity through which the trussrod was installed in the neck.
Commonly used set neck joints include mortise and tenon joints (such as those used by CF Martin & Co. guitars), dovetail joints (also used by CF Martin on the D28 and similar models) and Spanish heel neck joints which are named after the shoe they resemble and commonly found in classical guitars. All three types offer stability. Bolt-on necks, though they are historically associated with cheaper instruments, do offer greater flexibility in the guitar's set-up, and allow easier access for neck joint maintenance and repairs.
Guitar strings are strung almost parallel to the neck, whose surface is covered by the fingerboard (fretboard). By depressing a string against the fingerboard, the effective length of the string can be changed, which in turn changes the frequency at which the string will vibrate when plucked. Guitarists typically use one hand to pluck the strings and the other to depress the strings against the fretboard.
The strings may be plucked using either the fingers or a pick (or plectrum).
In electric guitars, transducers known as pickups convert string vibration to an electric signal, which in turn is amplified and fed to speakers, which vibrate the air to produce the sound we hear. Nevertheless, the body of the electric guitar body still performs a role in shaping the resultant tonal signature.
In an acoustic instrument, the body of th guitar is a major determinant of the overall sound quality. The guitar top, or soundboard, is a finely crafted and engineered element made of tonewoods such as spruce and red cedar. This thin piece of wood, often only 2 or 3mm thick, is strengthened by differing types of internal bracing. The top is considered by many luthiers to be the dominant factor in determining the sound quality. The majority of the instrument's sound is heard through the vibration of the guitar top as the energy of the vibrating strings is transferred to it.
Body size, shape and style has changed over time. 19th century guitars, now known as salon guitars, were smaller than modern instruments. Differing patterns of internal bracing have been used over time by luthiers. Torres, Hauser, Ramirez, Fleta, and C.F. Martin were among the most influential designers of their time. Bracing not only strengthens the top against potential collapse due to the stress exerted by the tensioned strings, but also affects the resonance characteristics of the top. The back and sides are made out of a variety of timbers such as mahogany, Indian rosewood and highly regarded Brazilian rosewood (Dalbergia nigra). Each one is primarily chosen for their aesthetic effect and can be decorated with inlays and purfling.
The body of an acoustic guitar has a sound hole through which sound is projected. The sound hole is usually a round hole in the top of the guitar under the strings. Air inside the body vibrates as the guitar top and body is vibrated by the strings, and the response of the air cavity at different frequencies is characterised, like the rest of the guitar body, by a number of resonance modes at which it responds more strongly.
The type and model of pickups used can greatly affect the tone of the guitar. Typically, humbuckers, which are two magnet/coil assemblies attached to each other are traditionally associated a heavier sound. Single coil pickups, one magnet wrapped in copper wire, are used by guitarists seeking a brighter, twangier sound with greater dynamic range.
Fender Stratocaster type guitars generally utilize 3 single coil pickups, while most Gibson Les Paul types use humbucker pickups.
Piezoelectric, or piezo, pickups represent another class of pickup. These employ piezoelectricity to generate the musical signal and are popular in hybrid electro-acoustic guitars. A crystal is located under each string, usually in the saddle. When the string vibrates, the shape of the crystal is distorted, and the stresses associated with this change produce tiny voltages across the crystal that can be amplified and manipulated.
Some piezo equipped guitars use what is known as a hexaphonic pickup. "Hex" is a prefix meaning six. In a hexaphonic pickup separate outputs are obtained from discrete piezoelectric pickups for each of the six strings. This arrangement allows the signal to be easily modified by on-board modelling electronics, as in the Line 6 Variax brand of electric guitars, the guitars allow for a variety of different sounds to be obtained by digitally manipulating the signal. This allows a guitar to mimic many vintage models of guitar, as well as output alternate tunings without the need to adjust the strings.
Another use for hexaphonic pickups is to send the output signals to a MIDI interpretation device, which determines the note pitch, duration, attack and decay characteristics and so forth. The MIDI (Musical Instrument Digital Interface) interpreter then sends the note information to a sound bank device. The resulting sound can closely mimic numerous types of instrument.
On almost all modern electric guitars, the bridge is adjustable for each string so that intonation stays correct up and down the neck. If the open string is in tune but sharp or flat when frets are pressed, the bridge can be adjusted with a screwdriver or hex key to remedy the problem. In general, flat notes are corrected by moving the bridge forward and sharp notes by moving it backwards. On an instrument correctly adjusted for intonation, the actual length of each string from the nut to the bridge saddle will be slightly but measurably longer than the scale length of the instrument. This additional length is called compensation, which flattens all notes a bit to compensate for the sharping of all fretted notes caused by stretching the string during fretting.
Leo Fender, who did much to create the electric guitar, also created much confusion over the meaning of the terms "tremolo" and "vibrato", specifically by misnaming the "tremolo" unit on many of his guitars and also the "vibrato" unit on his "Vibrolux" amps. In general, vibrato is a variation in pitch, whereas tremolo is a variation in volume, so the tremolo bar is actually a vibrato bar and the "Vibrolux" amps actually had a tremolo effect. However, following Fender's example, electric guitarists traditionally reverse these meanings when speaking of hardware devices and the effects they produce. See vibrato unit for a more detailed discussion, and tremolo arm for more of the history.
A distinctly different form of mechanical vibrato found on some guitars is the Bigsby vibrato tailpiece, commonly called A distinctly different form of mechanical vibrato found on some guitars is the Bigsby vibrato tailpiece, commonly called A distinctly different form of mechanical vibrato found on some guitars is the Bigsby vibrato tailpiece, commonly called Bigsby. This vibrato wraps the strings around a horizontal bar, which is then rotated with a handle by the musician.
Another type of pitch bender is the B-Bender, a spring and lever device mounted in an internal cavity of a solid body electric, guitar that allows the guitarist to bend just the B string of the guitar using a lever connected to the strap handle of the guitar. The resulting pitch bend is evocative of the sound of the pedal steel guitar.
Types of guitar - Electric guitars
Main article: Electric guitar
Seven-string solid body electric guitars were popularized in the 1980s and 1990s in part due to the release of the Ibanez Universe guitar, endorsed by Steve Vai. Other artists go a step further, by using an 8 string guitar with two extra low strings. Although the most common 7 string has a low B string, Roger McGuinn (Of Byrds/Rickenbacker Fame) uses an octave G string paired with the regular G string as on a 12 string guitar, allowing him to incorporate chiming 12 string elements in standard 6 string playing.
The electric bass guitar is similar in tuning to the traditional double bass viol. Hybrids of acoustic and electric guitars are also common. There are also more exotic varieties, such as guitars with two, three[11] or rarely four necks, all manner of alternate string arrangements, fretless fingerboards (used almost exclusively on bass guitars, meant to emulate the sound of a stand-up bass), 5.1 surround guitar, and such.
Some electric guitar and electric bass guitar models feature Piezoelectric pickups, which function as transducers to prSome electric guitar and electric bass guitar models feature Piezoelectric pickups, which function as transducers to provide a sound closer to that of an acoustic guitar with the flip of a switch or knob, rather than switching guitars.
Types of guitar - Acoustic guitars
Acoustic guitarsAn acoustic guitar is one not dependent on an external device to be heard but uses a soundboard which is a wooden piece mounted on the front of the guitar's body. The acoustic guitar is quieter than other instruments commonly found in bands and orchestras so when playing within such groups it is often externally amplified. Many acoustic guitars available today feature a variety of pickups which enable the player to amplify and modify the raw guitar sound.
There are several notable subcategories within the acoustic guitar group: classical and flamenco guitars; steel string guitars, which include the flat top or "folk" guitar; twelve string guitars and the arch top guitar. The acoustic guitar group also includes unamplified guitars designed to play in different registers such as the acoustic bass guitar which has a similar tuning to that of the electric bass guitar.
Renaissance and Baroque guitars These are the gracile ancestors of the modern classical guitar. They are substantially smaller and more delicate than the classical guitar, and generate a much quieter sound. The strings are paired in courses as in a modern 12 string guitar, but they only have four or five courses of strings rather than six. They were more often used as rhythm instruments in ensembles than as solo instruments, and can often be seen in that role in early music performances. (Gaspar Sanz' Instrucción de Música sobre la Guitarra Española of 1674 constitutes the majority of the surviving solo corpus for the era.) Renaissance and Baroque guitars are easily distinguished because the Renaissance guitar is very plain and the Baroque guitar is very ornate, with inlays all over the neck and body, and a paper-cutout inverted "wedding cake" inside the hole.
The type of resonator guitar with a neck with a square cross-section -- called "square neck" -- is usually played face up, on the lap of the seated player, and often with a metal or glass slide. The round neck resonator guitars are normally played in the same fashion as other guitars, although slides are also often used, especially in blues.
History
The modern guitar is descended from the Roman cithara brought by the Romans to Hispania around 40 AD, and further adapted and developed with the arrival of the four-string oud, brought by the Moors after their invasion of the Iberian peninsula during the 8th century AD.[4] Elsewhere in Europe, the indigenous six-string Scandinavian lut (lute), had gained in popularity in areas of Viking incursions across the continent. Often depicted in carvings c.800 AD, the Norse hero Gunther (also known as Gunnar), played a lute with his toes as he lay dying in a snake-pit, in the legend of Siegfried.[5] By 1200 AD, the four string "guitar" had evolved into two types: the guitarra morisca (Moorish guitar) which had a rounded back, wide fingerboard and several soundholes, and the guitarra latina (Latin guitar) which resembled the modern guitar with one soundhole and a narrower neck.[6]
The Spanish vihuela or "viola da mano", a guitar-like instrument of the 16th century, appears to be an aberration in the transition from the renaissance instrument to the modern guitar. It had lute-style tuning and a guitar-like body. Its construction had as much in common with the modern guitar as with its contemporary four-course renaissance guitar. The vihuela enjoyed only a short period of popularity; the last surviving publication of music for the instrument appeared in 1576. It is not clear whether it represented a transitional form or was simply a design that combined features of the Arabic oud and the European lute. In favor of the latter view, the reshaping of the vihuela into a guitar-like form can be seen as a strategy of differentiating the European lute visually from the Moorish oud.
The Vinaccia family of luthiers is known for developing the mandolin, and may have built the earliest extant six string guitar. Gaetano Vinaccia (1759 - after 1831)[7] has his signature on the label of a guitar built in Naples, Italy for six strings with the date of 1779.[8][9] This guitar has been examined and does not show tall-tale signs of modifications from a double-course guitar although fakes are known to exist of guitars and identifying labels from that period.
Modern dimensions of the classical instrument were established by Antonio Torres Jurado (1817-1892), working in Seville in the 1850s. Torres and Louis Panormo of London (active 1820s-1840s) were both responsible for demonstrating the superiority of fan strutting over transverse table bracing.[10]
The electric guitar was patented by George Beauchamp in 1936. Beauchamp co-founded Rickenbacher which used the horseshoe-magnet pickup. However, it was Danelectro that first produced electric guitars for the wider public.
Introduction
Guitars are recognized as one of the primary instruments in blues, country, flamenco, rock music, and many forms of pop. There is also a solo classical instrument. Guitars may be played acoustically, where the tone is produced by vibration of the strings and modulated by the hollow body, or they may rely on an amplifier that can electronically manipulate tone. Such electric guitars were introduced in the 20th century and continue to have a profound influence on popular culture.
Traditionally guitars have usually been constructed of combinations of various woods and strung with animal gut, or more recently, with either nylon or steel strings. Guitars are made and repaired by luthiers.