Guitar Scales Part 2
Pentatonic Scales
Minor Pentatonic Scale: 1-b3-4-5-b7
Blues Scale: 1-b3-4-b5-5-b7
Major Pentatonic Scale: 1-2-3-5-6
The minor pentatonic scale has played a major role in blues, rock, hard rock, metal, punk, and just about every genre influenced by any of those. It is actually a surprisingly bland version of the minor scale, but in proper hands, it can be used to create some really amazing guitar parts. The beauty of that particular scale is that it is so simple that a lot of issues that might crop up for something like Lydian or Locrian just don’t affect the minor pentatonic.
A small variation to it called the Blues scale is also quite common. Generally, it still gets lumped into the pentatonic scales, despite having six notes, rather than five. Arguably, it isn’t often even used as a scale in its own right, and the extra b5 note is just used for a passing tone between the 4 and 5 notes. Some musicians do make more use of that note than others though. It is still a useful scale to know about for blues and rock music.
The major pentatonic scale just doesn’t get used all that often. Pretty much the only example most people might be familiar with is the opening to “My Girl” by the Temptations, but it really just doesn’t seen anywhere near the usage of the minor pentatonic scale or the blues scale.
Harmonic Minor and Phrygian Dominant
Harmonic Minor Scale: 1-2-b3-4-5-b6-7
Phrygian Dominant Scale: 1-b2-3-4-5-b6-b7
The harmonic minor scale is an example of a scale that isn’t a mode of the major scale or simply a major or minor scale with notes removed. The big difference is that both of these scales incorporate an interval of three half steps between two notes in the scale (b6-7 for harmonic minor and b2-3 for Phrygian dominant). This creates a feel that can range from giving a rather classical feeling to a song to being quite dark, depending on how it is used. Phrygian Dominant is actually a mode of the Harmonic Minor scale (the only one commonly used), which demonstrates that not all modes are related to the major scale. Granted most guitarists won’t get much into more exotic scales, but it is a good idea to understand that there are scales and modes that are unrelated to the major scale.
There are a huge number of scales and modes out there, but at this point you should have a good idea of some of the more common ones. Depending on your style of music, you may very well only use the minor pentatonic and blues scales, but having a wider grasp can vastly improve the range of your playing and songwriting. A lot of glam rock bands brightened the minor pentatonic scale by incorporating the 6 note, and effectively playing the Dorian mode. Knowing little things like that can let you pull a lot more out of the scales and modes and help you break down some boundaries in your playing.