In this issue, we’re taking a look at the diminished scale. The diminished scale is an octatonic scale which contains eight notes, unlike the seven notes we usually use when playing the major or minor scale. A diminished scale is derived from a pattern of half and whole steps; the distance of one or two frets on the guitar. The diminished scale can start with a half step followed by a whole step, or vice versa. These two octatonic patterns have different applications, and in this issue, we will focus on the more common pattern of a half step followed by a whole step.
The half-whole diminished scale is used to solo over dominant seventh chords. Because it is most often used for that purpose, it is also referred to as the dominant diminished scale. Being a non-diatonic scale, it contains a lot of tension, making it a great scale to use as long as you practise it enough to know how to resolve that tension when required. The dominant diminished scale is also a great scale to write riffs with, especially if you make use of the two tri-tones – those are perfect for metal riffs. You will find the dominant diminished scale used in all styles of music, from rhythm and blues to jazz and metal.
I want to focus on its use as a technical exercise, and how it can be used to write riffs that sound darker and more tense than what can be derived from the major scale and its modes.
Exercise #1 outlines an ascending one-octave pattern of the dominant diminished scale. This pattern may require a position shift, given that is has four notes per string. Some players prefer to fret the four notes, but you’ll need exceptionally long fingers for that. I recommend playing just the first four notes on the E string until you work out what position shift works best for you. I prefer to shift up one fret with my first finger, as it gets me ready to shift over to the next string. Once you have your preferred position shift sorted, it’s just a matter of repeating that shift one fret higher on the A string.
As always, play with a click until you create a muscle memory. Getting this pattern down as one octave will make it easy to use over chord changes. I set up an iTunes playlist with one minute worth of metronome clicks that increase by ten beats per minute (bpm) with each new track. Start slow at 60bpm, and see if you can move up to 180bpm. Do this for a few days, and you should be able to do it in your sleep.
Exercise #2 outlines an ascending and descending sequenced pattern of the dominant diminished scale. This is a great pattern, as it is very linear with how it is fingered and it doubles as a great technical speed exercise. I finger the last four eighth notes of each bar as my first, second, third and pinky fingers. At speed, this pattern is a great warmup exercise. Try building up speed on the first bar until you have it well and truly under your fingers, and then play the pattern as it is written.
The best thing about diminished scales is that you can repeat the same pattern a minor third higher or lower, and you’ll end up with the same notes appearing in a different order. Exercise #3 outlines a onebar pattern that shifts up a minor third every two beats. This 16th note pattern flies by at 120bpm, but it’s a great technical exercise and very useful when you write a riff using the dominant diminished scale. Come up with your own riffs or technical patterns, and see how they sound when you shift them up or down by minor thirds. Hopefully, you can see the potential of this octotonic scale in adding a nondiatonic colour to your playing.