Chromatic Intervals
Not all intervals use notes from within a key. When an interval is formed between two notes that do not sit within a key, they are called chromatic intervals.
To find out the correct name for a chromatic interval, the diatonic interval names are modified and the following rules are used:
Raise a major interval by a semitone and it becomes an augmented interval.
Lower a major interval by a semitone and it becomes a minor interval.
Raise a perfect interval by a semitone and it becomes an augmented interval.
Lower a perfect interval by a semitone and it becomes a diminished interval.
See my video “Intervals – Part 2” for an explanation on how to apply this.
Intervals – Chromatic