C Db D Eb E F Gb G Ab A Bb B – Use these
C# D# E# Fb F# G# A# B# Cb – Toss these
Luckily for me I won’t be in a position where someone will hand me sheet music in some obscure key signature to read. The “use” line covers every note in the Western music chromatic scale. So if someone asks if I can improvise in F# major, I can confidently say yes. I have three options available 1) play in Gb because the notes sound almost exactly like F# 2) tune down a half step and play in G 3) through a capo on the first fret and play in F. I will almost always take option 1.
As you probably already know, C# is Db, D# is Eb, B# Cb C# E# and Fb are ridiculous, lastly G# is Ab. As guitarist, we are always just one fret away from the right scale.
I have made a commitment to learn the 12 “use” major scales and their related modes. That’s 84 scales. Luckily, the Aeolian scale is the natural minor so it is a freebie. Learning the harmonic and melodic minor scales is an additional 34. Yep, 108 scales right here.
If all goes well in 2022 maybe I will add additional scales to the list in 2023. If my head doesn’t explode!