In the last issue I talked about the symmetrical Whole tone scale. For this issue I thought I’d follow on from that and talk about another symmetrical scale – the Half-whole diminished scale. As with the Whole tone, the Half-whole diminished scale has an unconventional and ‘outside’ sound to it. Although it’s most commonly heard in jazz, it has a dissonant character to it that can sound cool for metal solos and riffs.


The scale is comprised entirely of an alternating series of half (H) and whole (W) steps. This can be seen in Exercise 1, shown here in the key of E on one string. Due to this repeating series of semitone and tone intervals, you get an eight note scale.

Hear Exercise 1


A great thing about the Half-whole diminished scale is that the fingering across the strings is really easy to remember. Here in the key of A, on the first string you use a 4-2-1 finger pattern and on the second string you reverse this for a 4-3-1 fingering. This is then repeated on strings three and four. You move up a fret for strings five and six but the finger groupings remain the same. It ends with a first finger position shift to the root note. To play it all over the neck, simply move the pattern up or down three frets at a time.

Hear Exercise 2


The scale is most often heard in a jazz context over an altered dominant seventh chord resolving to the tonic. This is because it contains the notes of a dominant seventh chord (1-3-5-b7) along with three of the four possible altered notes (plus a major 6th). The available chromatic notes to add to a dominant seventh chord are: b9, #9, b5, #5. The Half-whole diminished scale has the b9, #9 and b5. As such, its formula can be spelled as: 1-b9-#9-3-b5-5-6-b7. If this is a bit confusing, keep in mind that b9 is the same as b2, and #9 is the same as b3. Its use in jazz is illustrated in Exercise 3. Played with swung eighth notes in the key of D minor, A Half-whole diminished is used over the A7(b9) chord before resolving to the Dm7.

Hear Exercise 3


Putting all the theory aside, the scale just has a pretty sick and demented sound to it! This makes it great for writing cool riffs – be it single note or with power chords (as in Exercise 4). This is a simple, chugging riff that uses power chords based off of the first five notes of the Half-whole diminished scale.

Hear Exercise 4


This is a short lead phrase to be played with the riff from Exercise 4. The first two bars feature some standard minor scale licks to establish the overall E minor tonality. It then moves into an alternate-picked descending sequence using an E Half-whole diminished scale before resolving to the tonic. Although here it’s played over a riff based off the same scale, you can use the Half-whole diminished over any minor-key riff or chord progression. This is because while it does contain the notes of a dominant 7 chord (major), it also contains the notes of a minor 7 chord (1-b3-5-b7)and can be viewed as a natural minor scale but with the dissonant b2 and b5 intervals (plus a maj6 and maj3). As long as you don’t accentuate the ‘outside’ notes and resolve to a chord tone, it will work.

Hear Exercise 5

Alex Skolnick of Testament often employs the Half-whole diminished scale (as well as its cousin, the Whole-half diminished scale) in his solos. So check out some Testament for more examples, and give it a go yourself.