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In music
Music is generally defined as the art of arranging sound to create some combination of form, harmony, melody, rhythm or otherwise expressive content. Exact definitions of music vary considerably around the world, though it is an aspect ...
, a dyad (less commonly, diad) is a set
Set, The Set, SET or SETS may refer to:
Science, technology, and mathematics Mathematics
*Set (mathematics), a collection of elements
*Category of sets, the category whose objects and morphisms are sets and total functions, respectively
Electro ...
of two notes
Note, notes, or NOTE may refer to:
Music and entertainment
* Musical note, a pitched sound (or a symbol for a sound) in music
* Notes (album), ''Notes'' (album), a 1987 album by Paul Bley and Paul Motian
* ''Notes'', a common (yet unofficial) sho ...
or pitches that, in particular contexts, may imply a chord.
Dyads can be classified by the interval between the notes. For example, the interval between C and E is a major third
In classical music, a third is a musical interval encompassing three staff positions (see Interval number for more details), and the major third () is a third spanning four semitones. Forte, Allen (1979). ''Tonal Harmony in Concept and P ...
, which can imply a C major chord
In music theory
Music theory is the study of the practices and possibilities of music. ''The Oxford Companion to Music'' describes three interrelated uses of the term "music theory". The first is the " rudiments", that are needed to understan ...
, made up of the notes C, E and G.Young, Doug (2008). ''Mel Bay Presents Understanding DADGAD'', p.53. . When the pitches of a dyad occur in succession, they form a melodic
A melody (from Greek μελῳδία, ''melōidía'', "singing, chanting"), also tune, voice or line, is a linear succession of musical tones that the listener perceives as a single entity. In its most literal sense, a melody is a combinat ...
interval. When they occur simultaneously, they form a harmonic
A harmonic is a wave with a frequency that is a positive integer multiple of the ''fundamental frequency'', the frequency of the original periodic signal, such as a sinusoidal wave. The original signal is also called the ''1st harmonic'', the ...
interval.
The harmonic series is built over a fundamental pitch, and the rest of the partials in the series are called overtones. The second partial is an octave above the fundamental and the third pitch is a fifth, so if C is the fundamental pitch the second note is C an octave higher and then the next pitch would be G. The harmonic series has more fifths than just this one, for example the fourth to the sixth, the sixth to the ninth and the seventh to the eleventh partial are all a fifth away from each other, though the latter is of a slightly different size than the former ones.
See also
*Double stop
In music, a double stop is the technique of playing two notes simultaneously on a stringed instrument such as a violin, a viola, a cello, or a double bass. On instruments such as the Hardanger fiddle it is common and often employed. In performin ...
*Interval (music)
In music theory, an interval is a difference in pitch between two sounds.
An interval may be described as horizontal, linear, or melodic if it refers to successively sounding tones, such as two adjacent pitches in a melody, and vertical or h ...
*Power chord
A power chord (also fifth chord) is a colloquial name for a chord in guitar music, especially electric guitar, that consists of the root note and the fifth, as well as possibly octaves of those notes. Power chords are commonly played on am ...
*Harmonic series (music)
A harmonic series (also overtone series) is the sequence of harmonics, musical tones, or pure tones whose frequency is an integer multiple of a ''fundamental frequency''.
Pitched musical instruments are often based on an acoustic resonator su ...
*Counterpoint
In music, counterpoint is the relationship between two or more musical lines (or voices) which are harmonically interdependent yet independent in rhythm and melodic contour. It has been most commonly identified in the European classical tradi ...
References
Intervals (music) Simultaneities (music) {{Music-theory-stub