In music theory, a doubly diminished seventh is an interval that has four whole steps 
The doubly diminished seventh requires that:
- The interval must be an seventh interval (seven note names between the first and the last).
- The interval must have four whole steps.
What does a doubly diminished seventh look like?
Here is an example of a melodic doubly diminished seventh (two music notes in a melody) and a harmonic doubly diminished seventh (in a chord):
How to recognize a doubly diminished seventh?
Rule of music theory: All intervals in a major scale starting with the tonic (degree I) are either major or perfect, and only unison, octave, fourth and fifth are perfect (the others are major).
Example with the interval E / F♭♭:
Let's take the E flat major scale to have E as the tonic:
From the rule stated above, the interval E / F♯ is a major seventh, so the interval E / F is a minor seventh, so the interval E / F♭ is a diminished seventh, and so / F♭♭ is a doubly diminished seventh.
Inversion of the doubly diminished seventh
The inversion of the doubly diminished seventh is the doubly augmented second.
Here is an example of a doubly augmented second:
Musical examples of doubly diminished seventh
No examples yet, but feel free to send me some examples!
Interval identification game
You will find this interval in my Intervals identification game:
