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
Tenor guitar Freeman to have a better six string guitar sonority for rhythm guitar work than the normal tenor guitar with its very high A string. However, it was still tuned CGDA so that it could still be played by tenor banjoists. The Eddie Freeman Special was based on a six string model and it had a larger six string body and a six string scale length of 25.25 inches, rather than the tenor's smaller body and normal 23 inch scale length. The CGDA tuning used was re-entrant with the C and D tuned in the same octave and the G and