Ultraphrygian

Every degree lowered except the fifth

Set beside C major, Ultraphrygian keeps the root and the fifth and lowers everything else: the second, the third, the sixth and the seventh by a semitone each, and the fourth as well. Six of the seven notes sit below where the major scale puts them, which is why it reads as the darkest mode in the catalogue.

The fifth surviving matters more than it looks. A perfect fifth over the root means the scale still has a place to rest, unlike Locrian or the diminished modes. Ultraphrygian is unstable in colour but not in footing.

One note from Phrygian b4

Phrygian b4, the third mode of harmonic major, is 1 ♭2 ♭3 ♭4 5 ♭6 ♭7. Ultraphrygian matches it note for note except the seventh: minor there, diminished here. One note, two families, two different parent scales.

That note changes the chord. Phrygian b4 sits over a minor seventh; Ultraphrygian's thirds give C E♭ G B𝄫, which is a minor triad with a sixth. If a chart calls for a minor chord with a sixth in a dark passage, this is the scale; if it calls for a minor seventh, the other one is.

The flattened fourth

F♭ is the same key as E natural, and the scale already contains E♭ a semitone below it. Two notes that close together in the position where a chord decides between major and minor is the feature Ultraphrygian shares with Phrygian b4, and it is the reason both are written with a flat fourth rather than a major third.

Written as a third the notation would say the chord is major, which it is not: the fifth mode of the parent scale supplies the major third, this one does not. Spelling here is not pedantry; it tells the player which chord the line belongs to.

Where it comes from

The double harmonic scale is 1 ♭2 3 4 5 ♭6 7, a major scale with a flattened second and sixth, catalogued elsewhere as Byzantine, Arabic or Gypsy major. Reading it from the third degree gives Ultraphrygian, and both augmented seconds of the parent come along: F♭ to G, and B𝄫 to the octave.

Those two wide steps at the top of the scale are what identify the mode by ear. Descending from the octave the line drops three semitones twice in five notes, which no diatonic mode does even once.

Frequently asked questions