Music Theory
This guide covers music theory from the ground up, built specifically for guitar and bass players. Every concept connects directly to the fretboard — and every page has exercises you can do right now with the NeckSight tool.
Open the Fretboard ToolBeginner
Notes & Intervals
The 12 chromatic notes, semitones, named intervals, and why they're the foundation of every scale and chord.
Beginner
Scales & Keys
Major and minor scale construction, key signatures, and the relative major/minor relationship that connects them.
Beginner / Intermediate
Circle of Fifths
Why the circle is organized in perfect 5ths, how adjacent keys share almost all their notes, and how to use it for transposing and progressions.
Intermediate
The 7 Diatonic Modes
Modes are rotations of the major scale, not separate scales. Learn the parent scale concept and the brightness spectrum from Lydian to Locrian.
Intermediate
Chords & Triads
Triads, 7th chords, guide tones, and extended harmony — how chords are built from intervals and why the 3rd and 7th carry the harmonic identity.
Intermediate
Chord Progressions
Diatonic chords, Roman numeral notation, the Nashville Number System, and the mechanics behind why V always wants to resolve to I.
Intermediate
Writing Melodies
Target tones, chromatic approach notes, guide tones, and phrase structure — what separates a memorable melody from a scale run with no destination.
Advanced
Advanced Harmony
Modal interchange, secondary dominants, tritone substitution, and the Neapolitan chord — the tools of chromatic harmony and jazz reharmonization.
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