Example6 Tritone subs in three
Here we see how Emily might employ the ‘tritone’ substitution with a relaxed sense of groove and swing. The trick to this approach is to introduce an extra chord into each V-I resolution. Taking the G7 in bar 8 as an example, this would ordinarily resolve to some form of C chord, which it does in bar 10. However,
Db7, before we get to this C7 chord we see a tritone (three tones, or six frets) away from our initial G7, to produce a smooth descending semitone transition
Db from down to our target C7. This interchangeable quality is all possible as
Db7 Cb Db7, both G7 and share the same 3rd and 7th (B and F for G7, and F for enharmonically the same). If all this theory puts you off, please don’t worry. Given time this just becomes another sound that you’ll become comfortable with so listen carefully and you’ll spot the same sound used elsewhere in Emily’s playing and in the jazz genre overall.