Guitar chord for chords having their root note on the third, fourth, fifth, and sixth strings. For a six-string guitar in standard tuning, it may be necessary to drop or omit one or more tones from the chord; this is typically the root or fifth. The layout of notes on the fretboard in standard tuning often forces guitarists to permute the tonal order of notes in a chord. The playing of conventional chords is simplified by open tunings, which are especially popular in folk, blues guitar and non-Spanish classical guitar (such as English and Russian guitar). For example, the typical twelve-bar blues
Twelve-string guitar downward strum is the higher-octave string; 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 others 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