The Hypophrygian (deuterus plagalis) mode, literally meaning "below Phrygian (plagal second)", is a

musical mode In music theory, the term mode or ''modus'' is used in a number of distinct senses, depending on context. Its most common use may be described as a type of musical scale coupled with a set of characteristic melodic and harmonic behaviors. It ...

diatonic scale In music theory, a diatonic scale is any heptatonic scale that includes five whole steps (whole tones) and two half steps (semitones) in each octave, in which the two half steps are separated from each other by either two or three whole steps, ...

in medieval chant theory, the fourth mode of church music. This mode is the plagal counterpart of the authentic third mode, which was called '' Phrygian''. In the Middle Ages and Renaissance this mode was described in two ways: the diatonic scale from B to B an octave above, divided at the mode final E (B–C–D–E + E–F–G–A–B); and as a mode with final E and

ambitus In ancient Roman law, ''ambitus'' was a crime of political corruption, mainly a candidate's attempt to influence the outcome (or direction) of an election through bribery or other forms of soft power. The Latin word ''ambitus'' is the origin ...

from the A below to the C above. The note A above the final (the tenor of the corresponding fourth psalm tone) had an important melodic function. The melodic range of the ecclesiastical Hypophrygian mode therefore goes from the

perfect fourth A fourth is a musical interval encompassing four staff positions in the music notation of Western culture, and a perfect fourth () is the fourth spanning five semitones (half steps, or half tones). For example, the ascending interval from C to ...

or fifth below the tonic to the perfect fifth or minor sixth above. Greek Hypophrygian enharmonic genus

The name Hypophrygian originates in an

octave species In the musical system of ancient Greece, an octave species (εἶδος τοῦ διὰ πασῶν, or σχῆμα τοῦ διὰ πασῶν) is a specific sequence of intervals within an octave. In '' Elementa harmonica'', Aristoxenus classi ...

ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

music theory. According to

Aristoxenus Aristoxenus of Tarentum ( el, Ἀριστόξενος ὁ Ταραντῖνος; born 375, fl. 335 BC) was a Greek Peripatetic philosopher, and a pupil of Aristotle. Most of his writings, which dealt with philosophy, ethics and music, have been ...

, this octave species was originally described around the year 400 BC by the Harmonicist school of Eratocles in terms of the

enharmonic genus In the musical system of ancient Greece, genus (Greek: γένος 'genos'' pl. γένη 'genē'' Latin: ''genus'', pl. ''genera'' "type, kind") is a term used to describe certain classes of intonations of the two movable notes within a tetrach ...

of the

tetrachord In music theory, a tetrachord ( el, τετράχορδoν; lat, tetrachordum) is a series of four notes separated by three intervals. In traditional music theory, a tetrachord always spanned the interval of a perfect fourth, a 4:3 frequency pr ...

: a series of rising intervals of two quarter tones followed by a

ditone In music, a ditone (, from , "of two tones") is the interval of a major third. The size of a ditone varies according to the sizes of the two tones of which it is compounded. The largest is the Pythagorean ditone, with a ratio of 81:64, also cal ...

, together spanning a

. The Dorian octave species begins with this tetrachord, which is followed by a whole tone and another tetrachord to complete the octave with a pattern of ¼, ¼, 2, 1, ¼, ¼, and 2 tones. This pattern is rotated downward one degree for the Hypolydian, and one more for the Hypophrygian, for an octave species of 2, 1, ¼, ¼, 2, ¼, and ¼ tones. The name was appropriated by

Ptolemy of Alexandria Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importance ...

for one of his seven ''tonoi'', or transposition keys. Ptolemy's system differed from the earlier Aristoxenian model, which had thirteen transpositional levels each a semitone from its neighbours. Ptolemy substituted a diatonic sequence of seven transpositions pitched either a whole tone or a semitone apart. The entire double-octave scale system was then transposed onto each of these relative pitch levels, requiring (in modern terms) a different key signature in each case, and therefore a different sequence of whole and half steps in the fixed central octave span. The Hypophrygian transposition was the second-lowest of these, a whole tone above the Hypodorian. A whole tone higher was the Hypolydian, followed a semitone higher still by the Dorian, then after another whole tone by the Phrygian, and so on. Four centuries later, the term was taken from Ptolemy in exactly the same sense by

Boethius Anicius Manlius Severinus Boethius, commonly known as Boethius (; Latin: ''Boetius''; 480 – 524 AD), was a Roman senator, consul, ''magister officiorum'', historian, and philosopher of the Early Middle Ages. He was a central figure in the tr ...

, who described these seven names as "toni, tropi, vel modi" (tones, tropes or modes) in the fourth book of his ''De institutione musica''. In the late 9th century, in the Carolingian treatises ''Alia musica'' and in a commentary on it called the ''Nova expositio'', this set of seven terms, supplemented by an eighth name, "Hypermixolydian", was given a new sense, designating a set of diatonic octave species, described as the tonal embodiments of the eight modes of Gregorian chant. ''Missa Mi-mi'' (''Missa quarti toni'') by

Johannes Ockeghem Johannes Ockeghem ( – 6 February 1497) was a Franco-Flemish composer and singer of early Renaissance music. Ockeghem was the most influential European composer in the period between Guillaume Du Fay and Josquin des Prez, and he was—with hi ...

is a well-known example of a work written in the Hypophrygian mode.

References

Further reading