Light Beneath the Photic Zone — Improvisation in F Aeolian, A♭ Lydian & A♭ Lydian ♯2

In this video I am playing an improvised piece of music which I named Light Beneath the Photic Zone. The photic zone is the upper layer of a body of water and the furthest that sunlight can reach, enabling photosynthesis to take place. In the depths beneath the photic layer there is the dysphotic (twilight) zone, and the aphotic zone. The aphotic zone is the darkest of these layers and is reached by little to no sunlight, relying on the internalised light of bioluminescence. This is metaphorical for the idea of inner strength, self-generated motivation and innate knowledge; or finding purpose, hope and clarity in darkness. 

Light Beneath the Photic Zone – recorded 12th May 2026

In this piece of music, I started in the mournful F Aeolian mode, with a slow lamenting melody that gradually developed into subtle part-playing, with emphasis on inner voices — like a simultaneous voicing of the life in the sunlit, upper layer of water and that in the twilit dysphotic layer. Part-playing (or use of “inner voices”) in piano music is where more than one melody line is played simultaneously. 

At times the texture changed to fast broken chord figurations, like turbulence in the water. Sometimes there was a descending modal chord planing texture, like descending into the depths of the ocean, towards the aphotic zone.

A modulation to A flat Lydian brought more light due to the expansiveness of the distinctive raised 4th of the Lydian mode. Moving to A flat Lydian sharp 2 created paradoxical darkness and piercing light at the same time due to the harmonic minor character and jagged edge of the augmented 2nd, along with the bright sharpened 4th. Both the sharpened/raised 2nd and 4th degrees create an augmented interval from the tonic — i.e. an augmented 2nd and augmented 4th — literally expanding the intervals, destabilising and simultaneously brightening the sound. 

A return to F Aeolian for the final section brought variations of the earlier lamenting melodies, and then a final deeper descent of chord planing took the music further beneath the photic zone.

Modal Analysis Table 

ModeNote NamesParent ScaleModal Relationship
F Aeolian (Natural Minor)F, G, A♭, B♭, C, D♭, E♭A♭ Major6th Mode of A♭ Major
A♭ LydianA♭, B♭, C, D, E♭, F, GE♭ Major4th Mode of E♭ Major
A♭ Lydian ♯2A♭, B, C, D, E♭, F, GC Harmonic Minor6th Mode of C Harmonic Minor

Interval Formulas

  • Aeolian: 1, 2, ♭3, 4, 5, ♭6, ♭7
  • Lydian: 1, 2, 3, ♯4, 5, 6, 7
  • Lydian ♯2: 1, ♯2, 3, ♯4, 5, 6, 7

Further Reading and Listening

Learn more about modes in general here: Complete Guide to Modes of the Major, Melodic Minor, and Harmonic Minor Scales


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