The altered scale is a scale built from the sequence: semitone – tone – semitone – tone – tone – tone – tone.

We have already said in the article “melodic minor scale” that the altered scale of a chord can be constructed from the melodic minor scale one semitone above that chord. For example, the altered G scale is the melodic minor scale of G sharp. This makes our life easier, after all, we already know the melodic minor scale.

The notes that make up the G sharp minor melodic scale are: G#, A#, B, C#, D#, F, G

Shape of  G# Altered Scale:

what is altered scale

Note that this scale contains the notes G, B and F (fundamental, third and seventh of the G7 chord). The other notes: G sharp, A sharp, C sharp, D sharp are, respectively, ninth flat, ninth sharp, fifth flat and fifth sharp.

That is, all possible alterations to a dominant seventh chord are included in that scale. The chord generated by this scale can be G7#9#5, also known as G7alt. Note that the “alt” symbol is an abbreviation for “altered”, since its origins are in the altered scale. If you come across this “alt” notation out there, you already know what it is about (fifth and ninth sharp).

Note: although notes b5 and b9 also exist on this scale, the chord called “alt” does not refer to them, as these notes also mention the diminished scale, as we will see in the next topics.

Altered Scale application

The application of the altered scale we already demonstrated in the article “melodic minor scale”: it can be played over a altered dominant chord.

In terms of the generated sound, the altered scale produces one of the most complex sounds possible over a dominant. It is important to highlight here that playing the altered scale on top of an unaltered dominant can result in an unpleasant dissonance depending on the context. Therefore, it is essential to be aware of the effect produced. In altered dominants, there is no need for this concern.

The altered scale is one of the most widely used resources in jazz. If you intend to improve yourself in this style, it is essential to practice the altered scale a lot in different contexts of dominants to get used to its flavor.

But it is not just jazz that has altered dominants. Many other styles use these chords to exhaustion. An example of a very common occurrence is the dominant with #5 to appear before a minor chord with seventh and ninth, and a well-placed altered scale undoubtedly makes all the difference in these contexts.

We can risk saying that we have reached a hallmark. We are already addressing topics from professionals in the field. Get ready to become a full-blown musician! Study these patterns, improvise on top of the songs, apply, apply and apply.

These scales we’ve worked on so far need to be in your blood. But don’t face this training without motivation. It is essential that you have fun in this process. It is essential that you like the sounds generated, that you play with the ideas. Your musical personality needs to emerge. This is the moment!

Go to: Symmetric and asymmetric scales

Back to: Module 9