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
Touch guitar interactions with plectrums and fingers can all be mimicked digitally: in some cases, fret spacing and relationships can also be customized. Touch guitar The touch guitar is a musical instrument of the guitar family which has either been designed or adapted to use a fretboard-tapping playing style. Although "Touch Guitar" was registered as a trademark by musician and instrument designer Markus Reuter in the late 2000s, the term has been used formally or informally for a variety of instruments since the 1950s. The touch-style playing technique has been traced back to a variety of sources and players (including Merle Travis)