Half-diminished chords are difficult, but they don’t have to be. In How to Not Suck At Half-diminished Chords, I presented a simple way to start to improve at these often neglected chords and if you practiced the exercise in that article, you will without a doubt have made progress.
But even with some concentrated effort on those exercises, half-diminished chords are probably still giving you a tough time.
Why does this particular chord cause us so much trouble and what can we do about it?
The only reason half-diminished chords are difficult is because we’re given incomplete information about how to approach them. Jazz theory instructs us to play the locrian mode. So, what do we do with this information? We make a short cut so we can remember in real-time how to play over a half-diminished chord.
The line of thought goes something like this: Oh, B half diminished is just the locrian mode (7th mode) of C major. Great…that means whenever I see a half-diminished chord I’ll simply go up a half-step and play the major scale.
If that sounds like you, that’s why you suck at half-diminished chords. As How To Not Suck At Half-diminished Chords notes, the locrian mode is a starting place. That’s it.
And that being said, it’s actually a quite confusing starting place. Take for instance the half-diminished chord in this iii Vi ii V:
What does the B half-diminished chord have to do with C major? The answer: Nothing! That’s right. It has nothing to do with C major in this progression, so why would you think of it as a part of something completely unrelated?
Thinking of the B half-diminished chord as the locrian mode of C major will slow you down and confuse you time and time again.
The locrian mode trick is ...