Altered scale is made by the sequence: semitone – tone – semitone – tone – tone – tone – tone.
We already said, in the article “Melodic Minor Scale” that altered scale of a chord can be made through a melodic minor scale one tone above this chord. For example, the altered scale of G is the melodic minor scale of G#. This makes our life easier, because we already know the melodic minor scale.
The notes that make the melodic minor scale of G# are: G#, A#, B, C#, D#, F, G
Drawing of Altered Scale of G#
Notice that this scale has the notes G, B and F (fundamental, third and seventh of G7). The other notes: G#, A#, C#, D# are respectively, flatted ninth, sharp ninth, flatted fifth and sharp fifth. In other words, all the possible changes in a chord of dominant seventh are included in this scale.
Altered chord (alt)
The chord that is made by this scale we showed can be G7#9#5, also known as G7alt. You can notice that the symbol “alt” is the abbreviation of “altered” for having its origins in altered scale. When you face this notation “alt”, you already know what this is about (sharp fifth and ninth).
Observation: though the notes b5 and b9 also be in this scale, the named chord “alt” doesn’t refer to them, because these notes are also mentioned in diminished scale, as we will see in other topics.
Altered Scale application
We already showed the altered scale application in the topic “Melodic Minor Scale”: It can be played in an altered dominant chord.
In terms of given sound, the altered scale produces one of the most complex sounds in a dominant. It is important to highlight that playing an altered scale in a dominant that is not altered can result in an unpleasant dissonance depending on the context. For this, it is fundamental to be aware of the given effect. In altered dominants, this awareness is not needed.
The altered scale is one the most used in Jazz. If you want improve in this style, it is fundamental to practice a lot the altered scale in many dominant contexts to be used with its “flavor”.
But not only Jazz has altered dominants. Several other styles use and “abuse” of these chords. One example of really common occurrence is appearing the dominant with #5 before a minor chord with seventh and ninth, and an altered scale well placed, with no doubt, makes all the difference in these contexts.
We can risk saying that we arrive in a watershed. We are already addressing professional themes of the area. Prepare yourself to be a musician that masters it! Study these patterns, improvise them in songs, use them, and apply them, again and again.
Here bellow there is an example of Guitar Pro of Altered Scale (from the article “Melodic Minor Scale”):
These scales that we worked until here need “to be in your blood”. But don’t take this training without motivation. It is fundamental that you have fun in this process. It is fundamental that you like the produced sounds, and that you play with the ideas.
Your musical personality needs to flourish. This is the moment!
Go to: Module 9
Back to: Simplifying Theory