General theory

Here are some links to some of the key ideas underlying tuning:

Basics

• Ratio
  • Ratio math
• Cent
• Chords
• Scales
• Notation

Core concepts

• Just intonation
• Regular temperaments
• Equal-step tuning
• Periods and generators
• EDO
• EDT
• MOS scale
• Periodic scale
• Arithmetic tuning
• Comma pump

Javascript tools

Main article: List of Music Software#Browser Based

• Interval calculator – a nice online interval calculator tool, shows linear fraction and EDO fraction expansions, too
• An animated Javascript Moment of Symmetry (MOS) ring demo, another untwelve.org creation
• An excellent Firefox browser tuning demo synthesizer, 'Wicksynth'

Scales with few notes

• Category:5-tone scales
• Category:6-tone scales
• Category:7-tone scales
• Category:8-tone scales
• Category:9-tone scales
• Category:10-tone scales

Advanced theory

Main article: Mathematical Theory

• Chord of nature
• Cluster temperament
• Consonant class scale
• Diatonic, Chromatic, Enharmonic, Subchromatic
• Distributional Evenness
• Essential tempering commas
• Graham complexity
• Lumma stability
• Maximum variety
• Modal UDP Notation