Are doubly augmented and doubly diminished intervals practical?
In music theory when naming intervals, a lowered diminished interval is a doubly diminished interval (dd) and a raised augmented interval is a doubly augmented interval (AA). One example is a C♯ to a G♭ would be a doubly diminished 5th (dd5) and a C♭ to a F♯ would be a doubly augmented 4th (AA4). However, these intervals can be converted to their enharmonic equivalent so the make more sense so instead of having a C♯ to a G♭ you could write it as C# to F# and have it be a P4 and instead of having a C♭ to F♯ you could write a B to F# and have it be a P5. I have never actually seen a naturally occurring doubly diminished or doubly augmented interval I have only isolated examples in theory books. Is there ever any scenario where any doubly diminished or doubly augmented intervals are used in melodies or chords?
C - E - G = C - E flat - F# (and usually adds the note "A" for the doubly diminished 7th. ... C - E - G = C - E G# ... I love them; they make transitions and resolutions so rich. They're used all the time. They're great for VOICE-LEADING. And they only have the two inversions Music theory uses a lot of ENHARMONICS when naming intervals, a lowered diminished interval is a doubly diminished interval (e.g. "Coo") and a raised augmented interval is a doubly augmented interval (e.g. "C+").
