Twelve-string guitar
A twelve-string guitar (or 12-string guitar) is a steel-string guitar with 12 strings in six courses, which produces a thicker, more ringing tone than a standard six-string guitar. Typically, the strings of the lower four courses are tuned in octaves, with those of the upper two courses tuned in unison. The gap between the strings within each dual-string course is narrow, and the strings of each course are fretted and plucked as a single unit. The neck is wider, to accommodate the extra strings, and is similar to the width of a classical guitar neck. The sound, particularly on acoustic instruments, is fuller and more harmonically resonant than six-string instruments. The 12-string guitar can be played like a 6-string guitar as players still use the same notes, chords and guitar techniques like a standard 6-string guitar, but advanced techniques might be tough as players need to play or pluck two strings simultaneously.
This article is about guitars with six courses. For guitars with more than six separate strings, see Classical guitar with additional strings."Chorus" effect[edit]
The double ranks of strings of the 12-string guitar produce a shimmering effect, because even the strings tuned in unison can never vibrate with precise simultaneity—that is, they vibrate out of phase. The result to the ear is a sound that seems to "shimmer", which some describe as resembling strings that are slightly detuned. The interference between the out-of-phase vibrations produces a phenomenon known as a beat that results in a periodic rise and fall of intensity which is, in music, often considered pleasing to the ear. Pete Seeger described the distinctive sound of the 12-string guitar as "the clanging of bells."[1][2][3]
Design[edit]
The strings are placed in courses of two strings each that are usually played together. The two strings in each of the lower four courses are normally tuned an octave apart, while each pair of strings in the top two courses are tuned in unison. The strings are generally arranged such that the higher string of each pair is struck first on a downward strum. However, Rickenbacker usually reverses this arrangement on its electric 12-string guitars. The tuning of the second string in the third course (G) varies. Some players use a unison string, while most prefer the distinctive high-pitched, bell-like quality an octave string makes in this position. Another common variant is to tune the octave string in the sixth (lowest) course two octaves above the lower string, rather than one. Some players, either in search of distinctive tone or for ease of playing, remove some doubled strings. For example, removing the higher octave from the three bass courses simplifies playing running bass lines, but keeps the extra treble strings for the full strums. Some manufacturers have produced 9-string instruments based on this setup, in which either the lower three courses are singular, or the upper three courses are singular. Additionally; some players adapted more unconventional stringing: for example, Big Joe Williams used doubled strings on the 1st, 2nd and 4th courses of his guitars; at first adapted six-string instruments and into the sixties and later usually adapted 12-strings.
The extra tension placed on the instrument by the doubled strings is high, and because of this additional stress on their necks and soundboards, 12-string guitars long had a reputation for warping after a few years of use. (This is less of a problem in modern instruments, built after 1970.) Until the wide spread adoption by American makers of the truss rod after WWII, 12-string guitars were frequently tuned lower than the traditional EADGBE to reduce the stresses on the instrument. For example, Lead Belly often used a low-C tuning, but in some recordings, his tunings can be recognized as low-B and A tunings, partially due to the unusually long scale length (~26.5-27") of the particular models of guitar that he preferred in combination with the heavy strings that were commonly available (14-70).[28] Some 12-string guitars have nontraditional structural supports to prevent or postpone warping, at the expense of appearance and tone. To additionally reduce string tension, 12-string guitars built prior to 1970 typically had shorter necks and scale lengths than six-string guitars, which made frets more closely spaced, with some notable exceptions such as the instruments made by the Oscar Schmidt company before their bankruptcy, which usually had scale lengths of around 26.5". Their bridges, especially in acoustic guitars, had a larger reinforcement plate for the same reason, and tailpiece and floating-bridge setups were far more common than on six string instruments as another way to combat the effect of the high tension.
Advances in materials, design, and construction in such guitars made after 1970 have eliminated most of these accommodations. Contemporary 12 string guitars are commonly built to the same dimensions and scale as their six-string counterparts, albeit still usually with heavier build and bracing.[29]
Playing[edit]
The 12-string guitar's greater number of strings and higher cumulative string tension complicates playing, in both hands. Fretting chords requires greater force, and the width of the neck and the added string tension combine to make soloing and string-bending challenging. The gap between the dual-string courses is usually narrower than that between the single-string courses of a conventional six-string guitar, so more precision is required with the pick or fingertip when not simply strumming chords. Consequently, the instrument is most commonly used for accompaniment, though several players have taken the time to develop the 12-string guitar as a solo instrument. Flat-picking solos are more frequently seen with electric players, whereas a few acoustic players, such as Leo Kottke, have adapted fingerstyle techniques to the instrument; players such as Ralph Towner have applied classical playing techniques.
Roger McGuinn developed his own style of playing a 12-string guitar. The neck of a Rickenbacker 360/12 12-string guitar is as wide as the 6-string guitar. Solos are therefore easier to play and he used his banjo techniques to play chords. In addition to applying a compressor, this determined the sound of The Byrds. Lead Belly adapted both the traditional, simple strum style and the finger-style method that was becoming popular at the time as well; Blind Willie McTell also played finger-style 12 string.