Welcome to the latest installment of Chord by Chord, a series designed to build your understanding of harmony and the fretboard. In previous lessons, you’ve learned a bunch of different shapes for major and minor chords, and how to connect them. Now it’s time to tackle a new chord type—diminished.
Diminished chords have a dissonant sound and are often used to add tension to progressions. I’ll start by showing you how to transform A minor shapes into A diminished (dim).
The Work
As shown in Example 1, remember that a minor chord is comprised of three notes—the root, the minor third, and the fifth. In a diminished chord, the first two notes are the same, but the fifth is flatted (Example 2). On paper, this difference might seem subtle, but the variance in sound is actually pretty significant.
Example 3 makes use of the guitar’s middle strings, with the root note played on the open A string. In Example 4, we move a little further up the neck, still using the four middle strings with the open A. Note the use of the fourth finger on the Am chord, allowing for a smooth transition to the Adim. For a more conventional fingering on the Am, you could try using your third finger instead of your fourth.
In Example 5, you’ll use only the top three strings, but if you fingerpick, you could also include the root note on the open fifth string. Travel up to eighth position for Example 6. I suggest barring the top three strings with your first finger, so that you don’t have to move your whole hand when switching between the two shapes. Example 7, which is the highest on the neck but perhaps the easiest in this lesson, involves playing an Am chord on the top three strings and sliding the first-string E down a fret, to make Adim. Again, feel free to incorporate the open A.
The Result
By now you feel comfortable deriving Adim chords from various Am shapes. Keep in mind that in context, diminished chords usually play transitional roles. So instead of a demonstrating a song, I’ll just say that a classic example of the diminished sound is heard in old movie soundtracks, when a villain is tying someone, often a damsel in distress, to the railroad tracks as a train approaches. That’s it for this lesson—stay tuned for next time, when we’ll repeat the process with Em and Edim chords.
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