What is the Diminished Scale?

The diminished scale is a symmetric scale formed by the sequence: Tone – Semitone – Tone – Semitone – Tone – Semitone – Tone.

In the same way that we observed for the diminished chord, the diminished scale is repeated every three semitones. This is very advantageous, as it opens up a very wide range of possibilities. See an example of shape for the dimished scale of C below.

C Diminished Scale:

shape of the diminished scale

Notes: C, D, D#, F, F#, G#, A, B

Since this scale is repeated every three semitones, let’s check the diminished scale of D#:

d# diminished scale

Notes: D#, F, F#, G#, A, B, C

Note that, although these two scales start on different notes (one starts in C and the other starts in D#), both have the same notes.

Okay, and what’s the advantage of that? Well, let’s say you are improvising a solo in E minor until, at a certain point in the song, the B7 chord appears. As we will see later, you can use the C diminished scale over B7. But as this scale is identical to the D# scale, and D# is much closer to E than C, we can take advantage of this small distance and use the D# diminished scale (instead of C diminished) to make improvisation more fluent. This is one of the advantages.

Another advantage is the repetition of patterns on string instruments. You can make up a phrase on the diminished scale and repeat it every three semitones, creating a very interesting effect. Guitarist Yngwe Malmsteen explores this feature a lot. We will see this concept applied in the examples.

Now it’s time to show the application of this scale, after all, it’s useless to keep talking about it if what really matters is knowing where you can use these concepts!

How to use the Diminished Scale

As you might imagine, the diminished scale can be played over the diminished chord. This should not be strange, after all it is the diminished scale that forms the diminished chord. It is at this point that most students give up, after all the diminished chord does not appear as often in most musical styles; and when it does, it is mostly for a very short period, with no time for a diminished “phrase” to be developed. Then the student thinks: “Why am I going to waste time memorizing this scale if I will never use it?” And this is absolutely right! There is no point in memorizing things that will not be applied in practice.

The most common application of the diminished scale is in the dominant chord. It can be played a semitone above the dominant chord in question. In this case, the tonic (fundamental) of the dominant chord is played (that is, the scale starts with that note) and then the diminished scale is played a semitone above that tonic. We will explain this concept. Follow the logic:

Since this scale is repeated every three semitones, we can think about playing it starting from others degrees. For example, the G7 chord is a dominant that resolves in C major.

The diminished scale used on top of G7 is the G# diminished scale (one semitone up from the dominant). As this scale is repeated every three semitones, we can also play the B diminished scale (three semitones above G#).

Since B is one semitone below C, we can think that the diminished scale to be used is located one semitone below the chord that the dominant will resolve in.

In other words, it is as if we are “creating” an ascending passing diminished chord.  This is just one way of thinking, and it can be very useful in practice.

Imagine that you are improvising a solo in a song that is in C major, that is, you are using the C major scale. If the G7 chord ever appeared, it would be very practical to think about using the diminished scale one semitone below C, as it is very close to the region where you are playing your solo. Thinking about a scale one semitone above G7 can slow our response a little when improvising. But each person has their own preference. Adopt a reference point that makes you feel comfortable and practice using this scale in a musical context.

The dom-dim scale

Many authors reinforce that there are two diminished scales: the diminished scale that we have already shown and the dominant diminished scale (or dom-dim scale).

This dom-dim scale is nothing more than the diminished scale shape that we showed starting from the second degree instead of the first. That is, instead of the sequence being: tone-semitone-tone-semitone, etc; starting from the second degree, we will have: semitone-tone-semitone-tone, etc.

Notice now that we used exactly this second sequence on top of the dominant chords, because in the previous example we played the G# diminished scale starting from the G note, that is, the structure was semitone-tone-semitone-tone, etc.

Moral of the story: the dom-dim scale is the diminished scale applied on top of the dominant chord. Therefore, don’t think that they are different scales, just consider that it is the same diminished scale, only applied on top of the dominant (played a semitone above it). This will facilitate logic.

Create your own musical phrases and get fluent in this topic. It is very worthwhile to invest time in this study. The diminished scale is a fantastic feature; has a unique sound and enchants any listener.

Virtual diminished chord

Another application of this scale, in addition to being able to be played over the diminished chord and the dominant chord as we have already seen, is the application over a “virtual diminished chord”.

That’s right, don’t be alarmed! We are calling a virtual diminished chord a diminished chord that does not exist in the song, but one that could exist. It sounds crazy, but it is very simple.

Imagine that your band is playing a song that contains the chords | C | D | Em |, repeated in that sequence. After the D chord comes the E minor chord, but we have already mentioned on another article that the diminished chord goes very well as a passing diminished chord between a major and a minor chord (in this case, we would have the Major – Diminished – Minor sequence, being: D, D#°, Em). Obviously, we are not creating another bar, the diminished chord is just dividing the same bar as D.

Okay, this song doesn’t have this diminished chord, but we could play the sequence without any problems:

| C | D D#° | Em | instead of just playing | C | D | Em |, or even | C | D#° | Em | (completely suppressing the D chord).

The cool thing is that this passing diminished is so well accepted in this context that we can make a solo as if this chord were there, even if it is not there. In this case, we are deceiving the listener by making him believe that there is a diminished chord at that point. And the listener accepts it, because this progression is very pleasant!

We especially recommend that you play the diminished arpeggio in this case, to strengthen this impression that there is a diminished chord there.

Go to: Quartal Harmony

Back to: Module 9