Foundations
Music theory for people who think in grids and integers. It starts with air moving and ends at the piano roll, and along the way nothing is asserted: every rule arrives as a consequence of the one before it.
No notation, no guitar chords, no being told that something is correct because it sounds good. If you have ever wanted an answer to why that was not simply the name of the thing you asked about, this is that.
The derivation
The numbering is real. Each lesson establishes exactly one thing the next cannot proceed without, so they are meant to be read in order.
- 01SoundPressure waves, and the discovery that your ear measures pitch as a ratio rather than a difference.Establishes: Pitch is logarithmic in frequency, and the octave is 2:1.
- 02The harmonic seriesWhy a single note is never a single frequency, and what timbre actually is.Establishes: Every pitched sound is a stack of partials at integer multiples.
- 03ConsonanceWhy some intervals sound smooth and others grate, plotted rather than asserted.Establishes: Consonance is partial coincidence, and it depends on timbre.
- 04Stacking fifthsBuild a scale out of pure ratios and discover why it cannot be finished.Establishes: Pure ratios and free transposition are mutually exclusive.
- 05Equal temperamentTwelve notes as an engineering compromise, and exactly what it costs.Establishes: Why the grid has twelve steps, and which intervals pay for it.
- 06The gridEverything above, arriving in the piano roll as integer arithmetic.Establishes: Intervals are subtraction. On to chords.
Where the physics stops
Acoustics genuinely gives you the octave, the fifth, the major triad as 4:5:6, and an account of why some intervals grate. It does not give you the major scale uniquely, or functional harmony, or why a minor chord reads as sad. Those are convention, and partly learned.
A course claiming to derive all of music from physics is doing the same hand-waving as one that says the circle of fifths just works, only in a lab coat. Where the science is contested, these lessons say so.