What is a diminished interval?
Diminished intervals are a half step narrower than a perfect or minor intervals.
For instance, if there is an interval a half step narrower than a perfect 5th, we call it a diminished 5th. If there is an interval a half step narrower than a minor 6th, we call it a diminished 6th.
We will look into more details in this article.
I have to point out again just like when I talked about augmented intervals that narrower does not necessarily mean lower in pitch. You can make an interval narrower by raising the lower end of the interval as well. Just like the augmented intervals and #, some beginners assume they need to add a ♭ to make a diminished interval, but that is not always true.
As in the previous articles, I am attaching a diagram of a keyboard for your reference.
Diminished 3rd
When a minor 3rd gets narrowed by a half step, it becomes a diminished 3rd.
E♮ to G♭. E♮ to G♮ would be a minor 3rd. G♭ makes this interval a half step narrower, so it makes a diminished 3rd.
If the G♭ were written as a F#, the interval would be a major 2nd. E to F#, and E to G♭ sound the pretty much the same but they are completely different intervals in music theory.
A# to C♮. A♮ to C♮ would be a minor 3rd. A# makes this interval a half step narrower, which makes it a diminished 3rd.
Diminished 4th
Diminished 4th is an interval that is a half step narrower than a perfect 4th.
B♮ to E♭. B♮ to E♮ would be a perfect 4th. E♭ makes it a half step narrower, which makes the interval a diminished 4th.
D# to G♮. D♮ to G♮ would be a perfect 4th. D# makes this interval a half step narrower, making it a diminished 4th.
Diminished 5th
Diminished 5th is an interval that is half step narrower than a perfect 5th.
D♮ to A♭. D♮ to A♮ would be a perfect 5th. A♭ narrows the interval by a half step, making it a diminished 5th.
F# to C♮. F♮ to C♮ would be a perfect 5th. F# narrows the interval by a half step, which makes it a diminished 5th.
Diminished 6th
Diminished 6th is a half step narrower than a minor 6th.
B♮ to G♭. B♮ to G♮ would be a minor 6th. G♭ makes this interval narrower by a half step, making the interval a diminished 6th.
A# to F♮. A♮ to F♮ would be a minor 6th. A# makes the interval narrower by a half step, which makes it a diminished 6th.
Diminished 7th
Diminished 7th is a half step narrower than a minor 7th.
E♮ to D♭. E♮ to D♮ would be a minor 7th. D♭ makes the interval narrower by a half step, which makes the interval a diminished 7th.
G# to F♮. G♮ to F♮ would be a minor 7th. G# narrows the interval by a half step, making it a diminished 7th.
Now you know the intervals, keep practicing! Identify intervals whenever you play the violin. Make it into a habit to think of intervals when you play notes. Then associate the intervals with how they feel physically on the instrument, and how they sound in relation to each other.
Eventually, the intervals and the feel of physical distance will make a direct connection in your head, and you will be able to process it in realtime. When that happens, you will be able to play more in tune, and sight-read quicker. Playing the violin becomes more fun, and you will start to discover things you didn't notice before.
We have covered all of the basic intervals. Once you understand intervals, we can move onto other things like keys, scales, and chords. It is going to be even more fun to play music when you understand music theory, so let's keep learning!