(This was taken mostly from my book “Take Control: for
guitar”, available on Amazon)
Many rock songs consist of power chords built off of pentatonic
and blues scale roots. This is a style I first became aware of in
the early 70’s when I tried to figure out Black Sabbath songs.
All you do is pick a scale and play power chords built on those
notes. Since a power chord is just a perfect 5th interval and not
a complete chord, you don’t have to worry about those pesky
major and minor chords! Also songs in this style are mostly
played with lots of volume and distortion, so power chords are
plenty huge sounding. Generally the more “normal” the song
is, the more it sticks to pentatonic roots. The more “outside”
tunes add more extra blues notes. As you might guess with a
blues scale having so many options, the only way to keep the
key obvious is to keep hitting the root a lot. This explains why
so many heavy songs are based on E, you have to keep hitting
the root or the song turns into garbage. This means it’s easy to
tell what key the song is in (what note do they keep hitting?),
but a pain to figure out with all the options. Really heavy bands
do this trick with weird scales like diminished, whole tone,
synthetic modes, or whatever perverted sequence they can
dream up (Slayer). As for soloing, use whatever scale or note
sequence the power chords are built on, based on the root
they keep hitting. If all else fails, the pentatonic scale is your
friend. There are only 12 notes and it has to be one of them!
The diagram below shows an E pentatonic minor/blues scale
written on the 6th string. The extra blues tensions have an
asterisk beside them. Pick some frets, play them with power
chords and go crazy! Remember to keep hitting the root!
E PENTATONIC MINOR/BLUES SCALE
fret# string 6 note * blues tensions
0 E
1
2 F# *
3 G
4 G# *
5 A
6 A# *
7 B
8 C *
9 C# *
10 D
11
12 E
