Power chord

In music, a power chord (also fifth chord) is a chord consisting of only the root note of the chord and the fifth, usually played on electric guitar, and typically through an amplification process that imparts distortion. Power chords are a key element of many styles of rock music.

Analysis

When two or more notes are played through a distortion process which non-linearly transforms the audio signal, additional harmonics are generated at the sums and differences of the frequencies of the harmonics of those notes.

When a normal chord (for example, a major or minor chord) consisting of three or more different degrees of the scale is played through distortion, the number of different frequencies generated, and the complex ratios between them, can cause the resulting sound to be messy and indistinct.

However, in a power chord, the ratio between the frequencies of the root and fifth is simply 3:2 (see interval) . When played through distortion, this leads to the production of harmonics closely related in frequency to the original two notes, producing a more coherent sound. Additionally, the spectrum of the sound is expanded in both directions, producing a richer, more subjectively 'powerful' sound than the undistorted signal. With large amounts of distortion, the fundamental can appear to be an octave lower than the root note of the chord played without distortion, again giving a more bassy and powerful sound.

Even when played without distortion, the simple ratios between the harmonics in the notes of a power chord can give a stark and powerful sound.

Power chords also have the added advantage of being relatively easy to play (see "Fingering" below), allowing fast chord changes and easy incorporation into melodies and riffs.

Terminology

Theorists are divided on whether a power chord can be considered a chord in the traditional sense, with some requiring a 'chord' to contain a minimum of three degrees of the scale. When the same interval is found in traditional and classical music, it would not usually be called a "chord", and may be considered to be a dyad or simply an interval. However, the term is accepted as a pop and rock music term, most strongly associated with the overdriven electric guitar styles of hard rock, heavy metal, punk rock, and similar genres. 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.

Power chords are notated 5. For example, C5 (C power chord) refers to playing the root (C) and fifth (G). These can be inverted, so that the G is played below the C (making an interval of a fourth). They can also be played with octave doublings of the root or fifth note, which will make a sound that is subjectively higher pitched with less power in the low frequencies, but still retains the character of a power chord.

A power chord is neither major nor minor, as there is no third present. This gives the power chord a chameleon-like property; if played within the context of major chords, it will sound like a major chord, but when played with minor chords, it will sound minor.

Although the power chord is associated with a distorted sound, most guitarists would consider that a power chord fingering can be called a power chord whether played through distortion or not.

History

There is disagreement over which was the first record to feature power chords. Link Wray is commonly cited as having introduced power chords with his hit 1958 instrumental "Rumble". Wray used a pencil to punch holes into the loudspeaker of his amplifier in order to replicate a distortion effect first improvised at a show in Fredericksburg, Virginia. Wray pioneered electric guitar distortions, like overdrive and fuzz, and was the first guitarist to use power chords to play a song's melody.

However, power chords can also be found in earlier, less commercially successful recordings. Robert Palmer has argued that blues guitarists Willie Johnson and Pat Hare, both of whom played for Sun Records in the early 1950s, were 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).

A later hit song built around power chords was "You Really Got Me" by the Kinks, released in 1964. This song clearly demonstrates the fast power chord changes that would become typical of heavy rock riffs:

Early heavy rock bands such as Black Sabbath, Led Zeppelin and Deep Purple also helped to popularize power chords.

Pete Townshend, having been influenced by Link Wray, is often credited for introducing the term and the power chord in general and is an avid user of them.

Performance techniques

Power chords are often performed within a single octave, as this results in the closest matching of overtones. Octave doubling is sometimes done in power chords. Power chords are often pitched in a middle register. If they are too low, they tend to sound unclear and boomy. When played too high they lack depth and power.

Shown are four examples of an F5 chord. A common voicing is the 1-5 perfect fifth (A), to which the octave can be added, 1-5-1 (B). A perfect fourth 5-1 (C) is also a power chord, as it implies the "missing" lower 1 pitch. Either or both of the pitches may be doubled an octave above or below (D is 5-1-5-1), which leads to another common variation, 5-1-5 (not shown).

Pete Townshend of The Who is famous for his use of power chords. "My Generation", live versions of "I Can't Explain", and "Baba O'Riley" are good examples of the sound produced.

See also: Spider chord.

Fingering

Perhaps the most common implementation is I-V-I', that is, the root note, a note a fifth above the root, and a note an octave above the root. When the strings are a fourth apart, especially the lower four strings in standard tuning, the lowest note is played with some fret on some string and the higher two notes are two frets higher on the next two strings. Using standard tuning, notes on the first or second string need to be played one fret higher than this. (A bare fifth without octave doubling is the same, except that the highest of the three strings, in parentheses below, is not played. A bare fifth with the bass note on the second string has the same fingering as one on the fifth or sixth string.)

G5 A5 D5 E5 G5 A5 D5 A5 E||----------------------------------------------(10)---(5)----| B||--------------------------------(8)----(10)----10-----5-----| G||------------------(7)----(9)-----7------9------7------2-----| D||----(5)----(7)-----7------9------5------7-------------------| A||-----5------7------5------7---------------------------------| E||-----3------5-----------------------------------------------|

An inverted bare fifth, i.e. a bare fourth, can be played with one finger, as in the example below, from the riff in Smoke on the Water by Deep Purple:

G5/D Bb5/F C5/G G5/D Bb5/F Db5/Ab C5/G E||------------------------|----------------------| B||------------------------|----------------------| G||*--0---3---5------------|---0---3---6---5------| D||*--0---3---5------------|---0---3---6---5------| A||------------------------|----------------------| E||------------------------|----------------------|

|-----------------------|---------------------|| |-----------------------|---------------------|| |--0---3---5---3---0----|--------------------*|| |--0---3---5---3---0----|--------------------*|| |-----------------------|---------------------|| |-----------------------|---------------------||

Another implementation used is IV-I'-V', that is, a note a fourth below the root, the root note, and a note a fifth above the root. (This is sometimes called a "fourth chord", but usually the second note is taken as the root, although it's not the lowest one.) When the strings are a fourth apart, the lower two notes are played with some fret on some two strings and the highest note is two frets higher on the next string. Of course, using standard tuning, notes on the first or second string need to be played one fret higher.

D5 E5 G5 A5 D5 A5 D5 G5 E||-----------------------------------------------5------10----| B||---------------------------------10-----5------3------8-----| G||-------------------7------9------7------2-----(2)----(7)----| D||-----7------9------5------7-----(7)----(2)------------------| A||-----5------7-----(5)----(7)--------------------------------| E||----(5)----(7)----------------------------------------------|

With the drop D tuning--or any other dropped tuning for that matter--power chords with the bass on the sixth string can be played with one finger, and D power chords can be played on three open strings.

In order to maintain the alternating dominant and recessive notes, they almost never consist of more than 3 strings. D5 E5 E||---------------- B||---------------- G||---------------- D||--0-------2----- A||--0-------2----- D||--0-------2-----

Occasionally, open, "stacked" power chords with more than three notes are used in drop D.

E||--------------------------5--- B||--3-------5-------7-------3--- G||--2-------4-------6-------2--- D||--0-------2-------4-------0--- A||--0-------2-------4-------0--- D||--0-------2-------4-------0---

See also

Overtone

Intermodulation

Electronic tuner

Further reading

Crawshaw, Edith A. H. (1939). "What's Wrong with Consecutive Fifths?". The Musical Times, Vol. 80, No. 1154. (Apr., 1939), pp. 256-257.

References

External links

Guitar Lesson - Various power chord shapes and exercises

Category:Chords Category:Guitar performance techniques Category:Heavy metal performance techniques