SHREDDED METAL
MIXING MINOR MODES
The four most common minor-type scales/modes (excluding Minor pentatonic) are Aeolian (also known as Natural minor), Dorian, Phrygian, and Harmonic minor. Depending on the situation, it is possible to mix these four scales together when soloing (this is known as using parallel modes – different scales with the same root note). This could be over an extended static minor chord vamp, or over a standard minor key chord progression to create dissonance. However, in minor keys it is also common to mix the chords relating to these different scales. In this manner, different chords in the progression will imply different modes.
EXERCISE 1
These are the four common minor modes/scales, written here in the key of E using three note-per-string fingerings in the same position. The formula for each (in relation to the major scale) is as follows:
- Aeolian (1-2-b3-4-5-b6-b7); Dorian (1-2-b3-4-5-6-b7); Phrygian (1-b2-b3-4-5-b6-b7); Harmonic minor (1-2-b3-4-5-b6-7).
If you study these closely you will see that in comparison to Aeolian (the basic minor scale), for the other three scales only one note changes. Thus you can think of Dorian as Aeolian with a raised (#) sixth, Phrygian as Aeolian with a lowered (b) second, and Harmonic minor as Aeolian with a raised (#) seventh.
It is also important to understand the diatonic chord harmony for each of these scales. As triads this is:
- Aeolian (Im-IIdim-bIII-IVm-Vm-bVI-bVII); Dorian (Im-IIm-bIII-IV-Vm-VIdim-bVII); Phrygian (Im-bII-bIII-IVm-Vm-bVI-bVIIm); Harmonic minor (Im-IIdim-bIIIaug-IVm-V-bVI-VIIdim).
Notice how some chords stay the same whilst others change. By using Aeolian harmony as your base, you can substitute different chords from the other three minor scales into a progression (eg. IIm instead of IIdim = Dorian, bVIIm instead of bVII = Phrygian, etc). This will create subtle harmonic change whilst keeping the overall minor tonality. Although theoretically you could mix-and-match any of these chords, the most common progression for Dorian is Im-IV, Phrygian is Im-bII, and Harmonic minor is Im-V (commonly V7).
EXERCISE 2
To demonstrate this idea of mixing minor modes over a chord progression I’ve written a short study/etude. Although the overall key is E minor, each bar implies a different minor scale due to the chords that are used. Using the same fingerings from Exercise 1, the first bar is a Im-Vm progression (Em-Bm) which implies E Aeolian. The second bar, however, uses a Im-IV chord progression and denotes Dorian (since Aeolian would be Em-Am). The melodic line here starts with E Aeolian but changes to E Dorian on the A chord by raising the C to C#.
The following bar features a bII-Im change (F-Em) which implies Phrygian (the II chord for E Aeolian would be F#dim). The line descends/ascends using E Phrygian (F instead of F#) for the whole bar. The final bar uses a V7-Im progression. This indicates E Harmonic minor since when the 7th degree of Aeolian is raised to form Harmonic minor it also raises the third degree of the V chord and makes it major.
For space reasons I used two chords per bar for Exercise 2 and I wrote it in the style of a fast, sixteenth-note passage. However, you could slow it down and use one chord per bar (or more) to jam and improvise over this chord progression (or your own) to really get a feel for moving between the different scales. Mixing parallel minor modes and their chords is a great way to come up with some atypical solo ideas and chord progressions, and it is a cool concept to incorporate into your shred/metal solos.