Nocturne · StarBoard app 3 · Prototype 0.4.0

Scales and chords, by moonlight

Help me — how to use this

The keyboard, looking straight up. Pick a scale and every one of its keys lights from inside; pick a chord and see the shapes one hand — or two — can hold. Plug in a MIDI controller and Nocturne watches what you play.

Chart
Root
Scale / Mode
Note labels
Note spelling
Keyboard size
MIDI in Chrome or Edge, one permission click.

Charted scale

Scale

Scale notes Root in amber, every other degree in moonlight. Click a note to hear it.
Chords in this scale Stack the scale in thirds from each degree. Click one to light it inside the scale; chart it to see its voicings.
Colour from outsideBorrowed chords and secondary dominants — step out for a bar and come back. Click one to chart it.
Root Scale degree In the focused voicing Held on your controller

Keyboard

Chart export Save a colour PDF: the keyboard as it is now with every key named, then the chords in the scale and its fingering, or the voicings.

Listen

What you're playing

With a controller connected, held keys light on the keyboard above. Hold a chord and Nocturne names it; keep playing and it lists the scales that hold every note you've touched since the last clear.

Held now
Notes since clear

Observer's notes

What this prototype proves

The keyboard has no tuning to fight, so everything is a question of pitch: which keys hold the scale, which spell the chord, and which of those a hand can reach. Voicings come from stacking the chord tones and asking whether five fingers can span them; scales get their standard fingerings; a MIDI controller runs all of it backwards.

Nocturne remembers your last session in this browser: chart, keyboard size, display and spelling.