In
music theory
Music theory is the study of theoretical frameworks for understanding the practices and possibilities of music. ''The Oxford Companion to Music'' describes three interrelated uses of the term "music theory": The first is the "Elements of music, ...
, a minor seventh is one of two
musical intervals that span seven
staff positions. It is ''minor'' because it is the smaller of the two sevenths, spanning ten
semitones. The
major seventh
In music from Western culture, a seventh is a interval (music), musical interval encompassing seven staff positions (see Interval (music)#Number, Interval number for more details), and the major seventh is one of two commonly occurring sevenths. ...
spans eleven. For example, the interval from A to G is a minor seventh, as the note G lies ten semitones above A, and there are seven staff positions from A to G.
Diminished and
augmented sevenths span the same number of staff positions, but consist of a different number of semitones (nine and twelve, respectively).
Use
Minor seventh intervals rarely feature in melodies (and especially in their openings) but occur more often than major sevenths. A well-known example, in part due to its frequent use in theory classes, is found between the first two words of the phrase "There's a place for us" in the song "
Somewhere" in ''
West Side Story''.
Another well-known example occurs between the first two notes of the introduction to the
main theme music from ''
Star Trek: The Original Series''
theme.
The most common occurrence of the minor seventh is built on the
root
In vascular plants, the roots are the plant organ, organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often bel ...
of the prevailing
key's
dominant triad, producing the all-important
dominant seventh chord.
During the ''
common practice period'' the minor seventh was prescribed as a dissonance, requiring resolution to a consonance.
In other temperaments
In
just intonation
In music, just intonation or pure intonation is a musical tuning, tuning system in which the space between notes' frequency, frequencies (called interval (music), intervals) is a natural number, whole number ratio, ratio. Intervals spaced in thi ...
there is both a 16:9 "''lesser'' just minor seventh", also called the "Pythagorean small minor seventh",
[ ]() equivalent to two perfect fourths stacked on top of each other, and 9:5, called the "''greater'' just minor seventh" () equivalent to a perfect fifth and a minor third on top of each other. An interval close in frequency is the
harmonic seventh. ()
See also
*
Minor seventh chord
*
Musical tuning
*
List of meantone intervals
*
Harmonic seventh
References
{{DEFAULTSORT:Minor Seventh
Minor intervals
Sevenths (music)
no:Liten septim