OtoTheory

Learn Music Theory

11 guides that take you from "what's a chord?" to chord progressions, chord types, substitution, and borrowed chords. Written for guitar, bass, keyboard, and DAW users — no sheet music required.

1
What Is Music Theory? — Turning Feel into a Recipe
5min
2
What Are Intervals? (Beginner Level)
5min
3
What Are Chords?
5min
4
What Is a Key?
5min
5
What Are Scales?
5min
6
What Is Diatonic?
5min
7
The Science of Ear Training
5min
8
Learning Chord Progressions
5min
9
Expanding Your Chord Palette
5min
10
Dress Up Your Progressions with Substitute Chords
5min
11
Non-Diatonic Chords — Calling in Reinforcements from Outside the Team
5min
12
Slash Chords Explained: How One Bass Note Transforms Your Progressions
5min
13
Melody & Scales: Walking the Map
8min
14
The Pentatonic Scale: 5 Notes, Infinite Possibilities
8min
15
Tension Chords: Adding Color with 9ths, 11ths & 13ths
10min

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