all-interval tetrachord

File:All-interval tetrachords.png

An all-interval tetrachord is a tetrachord, a collection of four pitch classes, containing all six interval classes.Whittall, Arnold. 2008. The Cambridge Introduction to Serialism, p.271. Cambridge Introductions to Music. New York: Cambridge University Press. {{ISBN|978-0-521-86341-4}} (hardback) {{ISBN|978-0-521-68200-8}} (pbk). There are only two possible all-interval tetrachords (to within inversion), when expressed in prime form. In set theory notation, these are [0,1,4,6] (4-Z15)Schuijer, Michiel (2008). Analyzing Atonal Music: Pitch-Class Set Theory and Its Contexts, p.109. {{ISBN|978-1-58046-270-9}}. and [0,1,3,7] (4-Z29).Forte, Allen (1998), The Atonal Music of Anton Webern, p.17. {{ISBN|0-300-07352-6}}. Their inversions are [0,2,5,6] (4-Z15b) and [0,4,6,7] (4-Z29b).{{cite web |url=http://solomonsmusic.net/intstring.htm |url-status=dead |archive-url=https://web.archive.org/web/20060204234206/http://solomonsmusic.net/intstring.htm |archive-date=2006-02-04 |title=Interval String Table}} The interval vector for all all-interval tetrachords is [1,1,1,1,1,1].

Table of interval classes as relating to all-interval tetrachords

File:All-interval tetrachord dyads.png

File:All-interval tetrachord 4-Z15 diagram.svg

In the examples below, the tetrachords [0,1,4,6] and [0,1,3,7] are built on E.

class="wikitable"

|+ Interval class table for [0,1,4,6]

icnotes of [0,1,4,6] built on Ediatonic counterparts
1E to Fminor 2nd and major 7th
2A{{music|b}} to B{{music|b}}major 2nd and minor 7th
3F to A{{music|b}}minor 3rd and major 6th
4E to G{{music|#}}major 3rd and minor 6th
5F to B{{music|b}}perfect 4th and perfect 5th
6E to B{{music|b}}augmented 4th and diminished 5th

class="wikitable"

|+ Interval class table for [0,1,3,7]

icnotes of [0,1,3,7] built on Ediatonic counterparts
1E to Fminor 2nd and major 7th
2F to Gmajor 2nd and minor 7th
3E to Gminor 3rd and major 6th
4G to Bmajor 3rd and minor 6th
5E to Bperfect 4th and perfect 5th
6F to Baugmented 4th and diminished 5th

Use in modern music

The unique qualities of the all-interval tetrachord have made it very popular in 20th-century music. Composers including Frank Bridge, Elliott Carter (First String Quartet) and George Perle used it extensively.{{Citation needed|date=February 2012}}

See also

References

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