Music Theory Analysis #8
Opeth - "Blackwater Park" (title track)

1: Intro This song contains few chords, even fewer functional chords, and a wealth of different scales. Let's try an 'impressionistic' analysis.

2: Section I (1/2) Each individual chord change is diatonic in some key, but the lack of overarching key leads to a 'bleak' or 'wandering' sort of impression.

3: Section I (2/2) The accompanying melody is deceptively diatonic sounding. But this goes out the window in the chromatic transition to the next section.

4: Section II (1/2) The E Phrygian dominant scale gives a momentary impression of cohesion through a i / V change, but ends up settling on the iv chord.

5: Section II (2/2) The opening D Dorian #4 scale ends up being replaced by alternating very dark Locrian and very bright Lydian motifs that share a tritone.

6: Section III This riff is even more dark/bright, without any mediating thirds or minor 7ths. This is contrasted with a turnaround in D natural minor.

7: Section IV (1/2) A different approach to the dark/bright dichotomy using suspended chords and blues motifs to produce a dreamier, softer aesthetic.

8: Section IV (2/2) An interlude reverses the first Section I chord change into a chromatic descent, yet with a mismatched melody producing major features.

9: Section V This riff mostly commits to blues or Locrian features, but with a turnaround that has a major 6th, and later, Lydian features.

10: Section VI Another chromatic descent of minor chords, but unlike Section IV, its major third sees a minor 2nd, from the darker Phrygian dominant.

11: Section VII A Phrygian dominant figure rooted on the tritone suddenly switches to some tritone chords drawn from the C# whole tone scale.

12: Section VIII (1/2) A new riff uses the blues scale with an unconventional melodic shape, skipping over the tritone before jumping away to the minor 3rd.

13: Section VIII (2/2) This guitar solo ties together several of this song's motifs using a few closely related minor scales.

14: Section IX A chromatic mediant chord change underscores a melody using the melodic minor #4 scale, with notes similar to the C# whole tone.

15: Section X A combination of features, including contrasting Locrian/Lydian scales, and a melody that would fit over the Section I chord changes.

16: Section XI (1/3) A return to Section IX eventually heralds a switch to more unabashedly minor riffs using (to begin with) the Dorian #4 scale.

17: Section XI (2/3) More of the same, really emphasizing the scale's D diminished triad.

18: Section XI (3/3) A switch to more of a blues figure, though the riff also touches upon an Eb, suggesting the Locrian mode.

19: Section XII A subdued outro finally gives us functional harmony - in the natural minor key, but borrowing a chord from the darker Phrygian mode.

20: Conclusion (1/2) A collection of features from the song - some are not used with much consistency, so analysis must rely on impression rather than form.

21: Conclusion (2/2) A collection of 'informed impressions' - lots of dark/evil themes, though this is typical with truly expanded, non-functional harmony.