Guitar chord in the abstract musical-theory of chords for all instruments. For example, in the guitar (like other stringed instruments but unlike the piano), open-string notes are not fretted and so require less hand-motion. Thus chords that contain open notes are more easily played and hence more frequently played in popular music, such as folk music. Many of the most popular tunings—standard tuning, open tunings, and new standard tuning—are rich in the open notes used by popular chords. Open tunings allow major triads to be played by barring one fret with only one finger, using the finger like a capo. On guitars
Machine head among others, are cited as justification. This resistance remains despite the well-known issues with friction pegs losing tuning, coming loose, or jamming. In the early 2000s, a new type of machine head, utilizing micro-gearing inside of a friction-peg shaped casing that can be fitting to an instrument without physical alterations was introduced, and continues to be refined, but this technology is also facing resistance. Machine head A machine head (also referred to as a tuning machine, tuner, or gear head) is a geared apparatus for tuning stringed musical instruments by adjusting string tension. Machine heads are used on mandolins, guitars,