Seven-string guitar string is augmented with a high octave string. Many of McGuinn's notable guitar solos utilize the G string of the twelve-string guitar to perform the main melody, and therefore the Martin seven-string guitar was designed to achieve this extended range playing without the need for doubling all six of the guitar's strings. In 2010, Inox Guitars has created a mix of the Brazilian Viola caipira and the Russian semistrunka (семиструнка). This instrument has 2 bass strings (as the 6th and 7th strings of the semistrunka) and five treble courses (as the Viola caipira) and it is used in open tuning
Eight-string guitar too short, bridge problems such as improper intonation, uneven spacing for floating bridges, or the use of wrong string gauges. Other problems associated with tuning stability rely on proper set up of the guitar. Extended range eight string guitars sometimes will have a multi-scale design where the bass strings will be longer than the treble strings(fanned fret design). This helps with proper intonation of the lower strings, improves string tension balance across the strings, improves harmonic overtones, overtone series, and improves inharmonicity. (See also inharmonicity in pianos). The bass strings on an 8 string typically require the saddle to be