This Issue: Stacked 4ths
in issue 424 we tried systematically stacking pairs of 5th intervals to create chords, and we’re now going to try it with 4ths. if you normally approach chord substitution by learning shapes and swapping alternatives, you might find this a bit weird. We’ve always tried to show how you can approach chord knowledge from several angles. You might end up at the same place, but it’s all about the journey! to avoid an insane number of permutations we’re again going to work within the C major scale, using only perfect 4ths (ie not the augmented 4th between F and B) and we’re using the same ‘before’ chord progression as last time. You can of course apply your own rules – restrictions like this are a fertile source of creativity. There may be similarities to the chords you generate using 5ths, as 4ths and 5ths are closely related (C-G is a 5th; G-C is a 4th). However, the fretboard layout of the guitar means not every combination of either interval will be playable. By stacking two 4th intervals with a whole tone between them (C-F and G-C) we get sus2 chords. There’s no strict pattern to how we’ve replaced ‘vanilla’ chords with new chords; just play around and see what comes out! there’s a wider gap between the two 4ths this time. You’ll notice that the lower 4th interval corresponds with the 5th and root of the original chord in each case. Here we have B-E on the bottom (5th and root of Em) with D-G on top. not only do we have two 4th intervals, but they’re also separate by a gap of a 4th! This pure stack of 4ths is a bit of a 60s modern jazz cliché; at that time, there was a fashion for quartal harmony, building chords from 4ths. It sounds good, though. Finally, making use of the open strings we can have two 4th intervals (G-C and B-E) overlapping each other. Obviously an obstacle here is knowing enough chord theory to name your concoctions, but be brave. If a chord sounds like it’ll work in place of C major, that’s good enough. Trust your ears!