Power chord
Power chords are commonly played with an amp with intentionally added distortion or overdrive effects.
When played through distortion, the intermodulation leads to the production of partials closely related in frequency to the harmonics of the original two notes, producing a more coherent sound.
The intermodulation makes the spectrum of the sound expand in both directions, and with enough distortion, a new fundamental frequency component appears an octave lower than the root note of the chord played without distortion, giving a richer, more bassy and more subjectively "powerful" sound than the undistorted signal.
The use of the term "power chord" has, to some extent, spilled over into the vocabulary of other instrumentalists, such as keyboard and synthesizer players.
Although classical guitar composer Francisco Tárrega used it before him, modern musicians use Villa-Lobos's version to this day.
Robert Palmer pointed to electric blues guitarists Willie Johnson and Pat Hare, both of whom played for Sun Records in the early 1950s, as the true originators of the power chord, citing as evidence Johnson's playing on Howlin' Wolf's "How Many More Years" (recorded 1951) and Hare's playing on James Cotton's "Cotton Crop Blues" (recorded 1954).
[6] Scotty Moore opened Elvis Presley's 1957 hit "Jailhouse Rock" with power chords.
The Who's guitarist, Pete Townshend, performed power chords with a theatrical windmill-strum,[9][10] for example in "My Generation".
[11] On King Crimson's Red album, Robert Fripp thrashed with power chords.
Many punk guitarists used only power chords in their songs, most notably Billie Joe Armstrong and Doyle Wolfgang von Frankenstein.
Power chords are often performed within a single octave, as this results in the closest matching of overtones.
The chord or technique is used in the songs "Wake Up Dead", "Holy Wars...The Punishment Due", and "Ride the Lightning".
[13] As seen in the above tab, the two power chords may be played in succession without shifting, making it easier and quicker,[13] and thus avoiding string noise.
