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Learn & Train

Build your ears and your theory — recognition drills, an interactive music-theory track, and a set of psychoacoustic illusions. Every page plays what it shows.

Music theory

An interactive theory track from fundamentals through harmony, chromatic writing, and deep into jazz — each page is a tool and a lesson, spelled correctly and playable. From key signatures and voice leading to rhythm changes, Coltrane's major-third cycle, bebop lines, and the augmented sixths.

Fundamentals

Notes, the staff and clefs, accidentals and enharmonics on a playable keyboard, plus a key-signature reading drill. Start here.

Circle of Fifths

Every key a fifth apart — signatures, relative minors, and each key's diatonic chords by function. The map of tonal harmony.

Intervals

Build an interval and see it spelled on the staff (a minor third vs an augmented second), hear it, and drill your ear.

Chords

Triads through the seventh-chord family, inversions and figured bass — from a root and quality, or a typed jazz symbol.

Harmony

Roman numerals and tonal function in any key; build a progression and hear the cadence resolve.

Voice Leading

Four-part writing with a live checker: parallels, hidden fifths, crossing, spacing, and leading-tone errors, flagged as you move each voice.

Jazz Harmony

ii–V–I and guide-tone motion, the tritone substitution, extended and altered chords, and chord–scale pairings for improvising.

Modal Jazz

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Static harmony: sit on one mode's tonic chord instead of moving through a progression. Dorian, Phrygian, Lydian, and Mixolydian vamps, plus the classic half-step-up AABA shape behind "So What" and "Impressions".

Counterpoint

First-species counterpoint against a cantus firmus, graded live — consonances, no parallels, a proper stepwise close.

Rhythm & Meter

Read a random rhythm in any meter, hear it, then clap it back — scored on how close your taps land.

Score Reading

A clef-reading drill across treble, bass, and the C-clefs, plus a transposing-instrument tool for concert vs written pitch.

Scales & Modes

Build any scale spelled correctly, and see the seven modes ranked bright to dark with the one characteristic tone that colours each.

Non-Chord Tones

Passing and neighbor tones, suspensions, appoggiaturas, and anticipations — each decoration marked in context on the staff, and played.

Modulation

Change key by the pivot chord two keys share — named by its role in each — with the key relationship and a modulating cadence you can hear.

Chromatic Pre-Dominants

The Neapolitan sixth and the Italian, French, and German augmented sixths — the ♭6–♯4 that splays outward to V — spelled, highlighted, and resolved.

Tablature Reading

The fretboard as a pitch map: any (string, fret) to a spelled note across guitar, bass, and ukulele tunings, plus a tab line read onto the staff.

Composition Techniques

Grow a piece from one motif: invert it, reverse it, stretch or compress its rhythm — build a motif and hear each transformation against the original.

Chord–Scale Theory

Which scale voices each chord — Dorian over ii, Mixolydian or altered over V — with the guide-tone lines threaded through a ii–V–I.

Jazz Voicings

The same seventh chord as a shell, a rootless left hand, a quartal stack, and drop-2 / drop-3 spreads — spelled, shown on the staff, and played.

Upper-Structure Triads

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Stack a plain major triad over a dominant's guide tones and it becomes the chord's tensions. Type a dominant chord, pick a triad (II, ♭II, ♯IV, ♭VI, ♭VII), and see exactly which tension lands where.

Reharmonization

Same melody, new chords: tritone subs, secondary dominants, the backdoor ii–V, and modal interchange on a turnaround, with a before/after A–B player.

The Blues

The 12-bar form (three variants) in any key, the blue notes, and the blues scale — play the changes and solo over the top.

Rhythm Changes

The 32-bar AABA of “I Got Rhythm” in any key — the I–VI7–ii–V7 A section and the bridge's III7–VI7–II7–V7 cycle of dominants. Play a section or the whole form.

Coltrane Changes

“Giant Steps” logic: three tonal centres a major third apart, each major chord announced by its own dominant. Pick a key and hear the cycle turn.

Bebop Scales

The dominant, major, and Dorian bebop scales — one chromatic passing tone that keeps the chord tones on the downbeats. See which notes fall on the beat, and run it.

Walking Bass Lines

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A chord tone on beat 1, an approach tone into the next chord on beat 4: generate a rule-based line over a ii–V–I or a 12-bar blues, then edit any note and watch it get graded live.

Comping Rhythms

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The same chord, stated on every beat or held to one syncopated hit: Freddie Green's four-to-the-bar, the Charleston two-hit, a sparse off-beat comp, and a montuno. Hear the rhythm, not just the voicing.

Contrafacts

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A new tune over an old tune's changes: Anthropology, Oleo, and Rhythm-a-ning over Rhythm Changes; Countdown and 26-2 over Coltrane's own cycle. Searchable, with the changes playable and cross-linked to their source.

Melody Writing

Build a tune and get a live read on its shape — contour, range, steps vs leaps, and a single well-placed climax — then develop it.

Musical Form

Binary, ternary, rondo, theme-and-variations, sonata, and pop verse/chorus — each diagrammed and heard as a theme travels through it.

Arranging

Spread a chord across a section — concert vs written pitch for each transposing instrument, with out-of-range notes flagged.

Song Builder

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Plan a piece's shape under deadline — pick a form or genre, do the tempo⇄length math for the measures you need, map the instrumentation, and export the arrangement sheet.

Algorithmic Music

The history and landscape of music written as code — Csound, Max/MSP, SuperCollider, and the live-coding/algorave scene — a dedicated deep dive on browser-native Strudel, and a playable taste of the pattern-language style that powers it.

Algorithmic Music & Live Coding

From Xenakis's stochastic scores through Csound, Max/MSP, and SuperCollider to the algorave scene — a history and a filterable comparison of the tools.

Strudel

A deep dive on the browser-native live-coding language — how its pattern mini-notation works, plus official docs, learn-by-topic searches, and the people behind the scene.

Pattern Playground

Type a Tidal/Strudel-style pattern and hit Evaluate — a small, real live-coding mini-notation, built from scratch and playable right here.

Ear & Explore

Recognition drills, an interactive chord & scale explorer, and psychoacoustic illusions.

Ear Trainer

Recognition drills for intervals, chords, scales, inversions, and progressions — scored, with keyboard answers.

Chord & Scale Explorer

Scales, diatonic chords with roman numerals, and a melody-note harmonizer. Plays back.

Audio Illusions

Shepard–Risset glissando & rhythm, missing fundamental, binaural beats, tritone paradox, and Deutsch's octave/scale illusions.

Microtonal

The pitches between the piano keys — equal divisions of the octave (and the tritave), historical and world tunings, maqamat and thāts, just intonation and its commas, the harmonic series, acoustic beats, and Scala-file interchange. Exact playback, with .mid, MPE, .scl, .tun, and MTS export.

Equal Divisions of the Octave

Slide n to re-tune the keyboard, and see how 19, 31, or 53 equal steps approximate the pure intervals better than 12.

Historical & World Tunings

Meantone, Werckmeister, Kirnberger, just intonation, gamelan — plus the Arabic 24-tone, Turkish 53-koma, and Indian 22-shruti grids.

Maqam & Thāt Browser

Seven Arabic maqamat and the ten Hindustani thāts, played exactly on their own grids — neutral thirds, pure-ratio shrutis and all.

Just Intonation

Pure whole-number ratios on a clickable 5-limit lattice — and the commas, the tiny gaps where purity refuses to close.

Interval Microscope

One interval under the lens: just, Pythagorean, meantone, and four EDOs pinned to a zoomed cents ruler, each playable.

Harmonic Series

Partials 1–16, each with its distance from the nearest piano key — play the series, then watch a timbre assemble itself.

Beating & Ombak

Detune a pair and hear the beats — piano-tuner arithmetic, and the deliberate gamelan shimmer.

Scala Import & Export

Drop any .scl scale file, hear it exactly, and export .scl, .tun, MTS sysex, or MPE .mid — the microtonal interchange bay.

Music technology

How the tools of the trade actually work — the plugin formats a DAW hosts, and the per-note expression behind MPE and the new CLAP standard.

Plugin Formats

VST, AU, AAX, LV2 and the open new CLAP standard — what separates them, why CLAP exists, and which DAWs can host it. Filter to compare.

Note Expression & MPE

Play a chord and hear the difference between channel-wide modulation and per-note expression — the idea under MPE, MIDI 2.0, and CLAP.

MIDI — History & Anatomy

From the 1983 NAMM handshake to MIDI 2.0 — the full story, plus the bytes themselves: play a key and watch the message it makes, bit by bit.

Community

Music-making is a conversation — the forums, Discords, channels, and free references where it happens.

Community

A big curated linkroll by category — forums (Audiobus, Gearspace, KVR…), subreddits, Discord servers, YouTube channels, blogs & news, podcasts, and free interactive references.

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