Guitar Fretboard Mastery (Fret Science System)

A systematic approach to guitar theory emphasizing geometric patterns and understanding over rote memorization.

Core Concept: The Warp

The most important fretboard concept: the G-B string boundary shifts patterns by one fret.

• Standard tuning uses perfect 4ths (5 semitones) between strings, EXCEPT G-to-B which is a major 3rd (4 semitones)
• Any pattern crossing G↔B shifts one fret toward the bridge (G→B) or toward the nut (B→G)
• This explains why chord shapes change when moved across strings

Pentatonic Scale: Rectangle & Stack

The pentatonic scale is a 5-string repeating pattern with two geometric shapes:

The Rectangle (Red)

• Two notes on adjacent strings spanning 3 frets each
• Contains: 1, 5, b3, b7 (minor) or 6, 3, 1, 5 (major)
• Both right-hand notes can be bent a full step

The Stack (Blue)

• Three adjacent strings with 2-fret intervals
• Contains: b3, b7, 4, 1, 5 (minor) or 1, 5, 2, 6, 3 (major)
• Top-right corner bends full step; lower-right notes bend 1.5 steps

Navigation

• Rectangle and stack alternate vertically in each pentatonic form
• Rectangle and stack alternate horizontally with slight diagonal descent
• Stack connects diagonally to itself one octave higher (Clapton pathway)

Five Forms

All forms derive from shifting the 5-string repeating pattern up strings (accounting for warp): Form 1 → Form 4 → Form 2 → Form 5 → Form 3 → Form 1

Modes: Pentatonic + Fill-in Notes

Six modes are pentatonic scales with two notes added inside the rectangle:

Locrian (b5) doesn’t fit this system—it’s not built on major/minor pentatonic.

Brightness Order (each differs by one semitone)

Lydian (#4) → Ionian → Mixolydian (b7) → Dorian (b3,b7) → Aeolian (b3,b6,b7) → Phrygian (b2,b3,b6,b7) → Locrian

3nps (Three-Notes-Per-String)

A 7-string universal pattern with only 3 fingering shapes:

• 1-2-4 (half-whole): Scale degrees 7, 3
• 1-3-4 (whole-half): Scale degrees 6, 2
• 1-3-5 (whole-whole): Scale degrees 5, 1, 4

Phone Numbers for String Movement

• Going UP: 7-3-6-2-5-1-4
• Going DOWN: 4-1-5-2-6-3-7

Pattern 4→7 transition shifts one fret (can combine with warp for 2-fret shift).

String Pairs (for horizontal movement)

Memorize the 7 pairs—great for melodic sequences:

• Pair 1: 4/1 → 5/2 → 6/3 (same shape as Pair 5)
• Pairs 2-7 follow sequentially

CAGED System

Five open chord shapes (C-A-G-E-D) become a pegboard for the entire fretboard.

Root Locations

Memorize where roots fall in each CAGED shape—snap any pattern onto these positions.

Layered Hierarchy (for improvisation)

1. Root — Home base, most stable
2. Triad (1-3-5) — Always consonant, great phrase endings
3. Pentatonic — Adds melodic options
4. Mode — Full color palette

Triads

Four Types (stacked thirds)

Inversions

• Root position: 1-3-5
• 1st inversion: 3-5-1
• 2nd inversion: 5-1-3

Nine closed-form shapes exist (3 inversions × 3 string groups, warped versions for G-B crossing).

Quick Modifications

From Major: lower 3rd → minor, raise 5th → augmented, lower root 1 fret → maj7, lower root 2 frets → dom7 From Minor: raise 3rd → major, lower 5th → diminished, lower root 2 frets → m7

Intervals

Counting System

• Horizontal: +1 fret toward bridge, -1 toward nut
• Vertical: +5 per string up (toward floor), -5 per string down
• Warp crossing: count diagonally

Reference Table

9th = 2nd, 11th = 4th, 13th = 6th (subtract 7)

Harmonization with Thirds

Which Scale Degrees Get Major/Minor Thirds

• Major thirds (4 frets): 1, 4, 5
• Minor thirds (3 frets): 2, 3, 6, 7

Technique

1. Play melody on one string
2. Add third on adjacent string (major or minor based on scale degree)
3. Keep one finger anchored, shift other finger for major/minor

Spread Thirds with Pedal Tone

Capture open string as pedal, play thirds 2+ strings away. Assign scale degree to the note matching the open string to create any modal sound.

Circle of 4ths/5ths

Vertical Movement

Moving up a string = up a 4th (clockwise on circle) Moving down a string = down a 4th (counterclockwise)

The Sequence

4ths: B-E-A-D-G-C-F-Bb-Eb-Ab-Db-Gb 5ths: Reverse order with sharp names

Wraps diagonally around fretboard due to warp.

Fretboard Memorization Exercises

1. Combine with pentatonic: Find note everywhere using octave jumps, build pentatonic each time
2. Follow progressions: Find roots and build triads for each chord in a song
3. Cycle of 4ths on one string: Play B-E-A-D-G-C-F-Bb-Eb-Ab-Db-Gb
4. Chromatic one-note-per-string: Move chromatically while changing strings

Octave Shapes (CAGED Backbone)

Two “chess moves” for octave jumps:

• +2 strings, +2 frets (no warp) → +3, +2 with warp
• +2 strings, -3 frets (no warp) → +2, -3 with warp

These shapes connect CAGED positions.

For detailed diagrams, fingering charts, and visual references, consult the references/ folder.