piano scale
A altered
A1B♭♭2C♭3D♭♭4E♭♭5F♭6G♭7
The seventh mode of melodic minor. Every degree above the tonic that can be altered, is.
Written out
Every accidental is written in, rather than left to a key signature, so the letters can be read one at a time.
The step pattern
AHB♭WCHD♭WE♭WFWGWA
What is true of it
A altered is A, B♭, C, D♭, E♭, F and G, and back to A.
Its steps are H – W – H – W – W – W – W, where W is a whole step and H a half.
On the same tonic, A Locrian differs from it by exactly one note.
Chords made only of these notes
CmminorCm7minor seventhD♭augaugmentedE♭majorE♭7dominant seventhFmajorFaugaugmentedF7dominant seventh
Found by testing every chord in the catalogue against these 7 sounds, not chosen.