make a custom neck with a specific microtonal fret spacing. Guitars can also be refretted to a microtonal scale. On many refretted microtonal guitars, the frets are split, so that the tuning of each string is independent from the others. To enable an adjustable microtonal tuning, there exist guitars with frets that can be moved across the fingerboard. Extended techniques such as the 3rd bridge technique, slide guitar and prepared guitar techniques can be used to produce microtonality without severe modification to the instrument. Guitar tunings inspired by other Instruments In his on-line guide to alternative tunings for six-string guitars, William Sethares mentions several that are inspired by instruments other than guitars, for example: balalaika tuning: E-A-D-E-E-A cittern tuning: C-G-C-G-C-G, Dobro tuning: G-B-D-G-B-D. Renaissance lute tuning: E-A-d-f-b-e' This tuning may also be used with a capo at the third fret to match the common lute pitch: G-c-f-a-d'-g'. This tuning also matches standard vihuela tuning and is often employed in classical guitar transcriptions of music written for those instruments, such as, for instance, "La Canción Del Emperador" and "Diferencias Sobre Guardame Las Vacas" by Renaissance composer Luis de Narváez. Five-string guitar tunings When the guitar evolved from the renaissance lute in the 18th century it was a five-string instrument (baroque guitar). Today, five-string guitars are common in Brazil, where they are known as guitarra baiana and are typically tuned in 5ths. Schecter Guitar Research produced a production model five-string guitar called the Celloblaster in 1998. A five-string tuning may be necessary in a pinch when a string breaks on a standard six-string (usually the high E) and no replacement is immediately available. Some basic five-string tunings include:Standard - E-A-d-g-bThe standard tuning, without the top E string attached. Alternative variants are easy from this tuning, but because several chords inherently omit the lowest string, it may leave some chords relatively thin or incomplete with the top string missing (the D chord, for instance, must be fretted 5-4-3-2-3 to include F#, the tone a major third above D).Baroque guitar standard tuning – a–D–g–b–e The predecessor of today's six-string classical guitar was the five-string baroque guitar tuned as the five high strings of a six-string guitar with the A highered one octave.High C - E-A-d-g-c'Standard tuning with the B tuned a half step higher to C to emulate a six-string bass guitar, minus the low B. This is an all fourths tuning.Celloblaster or Guitello