Bass guitar the 3rd, 5th, 7th, 9th fret and 12th fret (the 12th fret being the octave of the open string) and on the octave-up equivalents of the 3rd fret and as many additional positions as an instrument has frets for. Typically, one marker is on the 3rd, 5th, 7th and 9th fret positions and two markers on the 12th fret. The long scale necks on Leo Fender's basses—with a scale length (distance between nut and bridge) of — set the standard for electric basses, although "short scale" instruments, such as the Höfner 500/1 "violin bass" played by Paul McCartney, and the
Ten-string guitar has a single neck and allows all strings to be fretted. While the six-string classical guitar remains the standard and most common instrument, since 1963 ten-string guitars in similar configuration to the original Ramírez have been adopted by many classical guitarists and produced by several first-class luthiers, using both Yepes' original tuning and others. The Halo Guitars XSI is a solid body ten-string guitar with ten individual steel strings, two EMG ten-string pickups, and a Kahler ten-string tremolo bridge. XSI is an acronym for Extended Scale Instrument. Halo Guitars tunes the XSI from low to high as follows: A+D+G+C+F-B♭-E♭-A♭-C-F. Agile