2 thoughts on “Secrets of Guitar Tuning”

I’m working with  on the next installment of , our ultra-futuristic online music theory course. The first unit covered the black keys of the piano and the pentatonic scales. The next one will talk about the white keys  and the . We were gathering examples, and we needed to find a well-known pop song that uses . My usual go-to example for Lydian is “” by Björk. But the course already uses a Björk tune for different example, and the Soundfly guys quite reasonably wanted something a little more millennial-friendly anyway. We decided to use Katy Perry’s “Teenage Dream” instead.

A couple of years ago, Slate ran by . It’s an okay explanation, but it doesn’t delve too deep. We thought we could do better.

Here’s my transcription of the chorus:

When you look at the melody, this would seem to be a straightforward use of the B-flat major scale. However, the chord changes tell a different story. The tune doesn’t ever use a B-flat major chord. Instead, it oscillates back and forth between E-flat and F. In this harmonic context, the melody doesn’t belong to the plain vanilla B-flat major scale at all, but rather the dreamy and modernist E-flat Lydian mode. The graphic below shows the difference.

Both scales use the same seven pitches: B-flat, C, D, E-flat, F, G, and A. The only difference between the two is which note you consider to be “home base.” Let’s consider B-flat major first.