Four singers on one square. Soprano, alto, tenor and bass, each cast as an element and a humour, blended with a single puck. The name is the ancient word for a perfectly balanced temperament, the point at the centre of the pad.
After Zarlino (1558), who likened the bass to earth, the tenor to water, the alto to air and the soprano to fire.
Playable prototype
The humour square
Across is hot to cold, down is dry to moist. Each corner is one singer. Press and drag anywhere on the square to sing the chord, and the puck's position sets how much of each temperament you hear.
Choleric
Silent
Marzia leads
Harmony in D minor · keys 1–6
AEIOU
Humour LFO · locked to the clock · S cycles
Choir strips · each singer's elemental effect
Voice realism
Each singer is now a small section of voices built from glottal pulses, the shape of air leaving real vocal folds, instead of two sawtooth waves. Effort sets how hard the pad sings: soft is darker and breathier, loud is brighter and pressed. MIDI uses note velocity instead. Breath mixes in air noise that pulses at each voice's pitch and passes through the vowel. Humanize sets the tiny pitch and loudness wobble, how far apart the section is tuned, and how unevenly its members enter. Vibrato bloom is how long a note stays straight before the vibrato opens up. Scoop is how far below a note each singer starts before settling, with a small overshoot. Bare turns all of it off so you can hear the difference.
Tuning · how the choir locks in
Dm ·
Equal temperament splits the octave into twelve identical steps, so every interval except the octave is slightly out, and thirds beat audibly. Adaptive just finds each chord's root and retunes every singer to a whole-number ratio above it, the way an a cappella group sings: fifths at 3:2, major thirds at 5:4, minor thirds at 6:5. The root stays on its equal-tempered pitch so the key never drifts. Held notes glide into tune at each singer's own pace; Marzia snaps in, Lunaro drifts. Fixed tunings use one set of ratios on the tonic for every chord, so some chords ring and others sour. Scala loads any .scl file with degree 0 on the tonic, including scales that aren't twelve notes.
Score player · MIDI
Chorale in D minor · 0:00 / 0:00
Drop a .mid file anywhere on this panel. Files with two to four single-line parts are assigned by pitch, highest to Marzia and lowest to Saturnino. Anything chordal, like a piano part, is split into four voices note by note. Every note is folded into its singer's range, and during playback the humour square sets who leads.
MIDI · in, out and clock
No MIDI devices connected. The clock below runs internally until you connect.
Clock
1.196.0 BPM · running
Nothing held
In: hold up to four notes and they're split across the choir, highest to Marzia and lowest to Saturnino; fewer notes are doubled. Sustain holds, pitch bend bends ±2 semitones, the mod wheel sweeps the vowel, and CC 16 and 17 move the puck across and down the square. Out: each singer sings on their own channel, so you can double the choir on any synth. Turn on pitch bend and that synth follows the adaptive tuning too (set its bend range to ±2). Clock: the Humour LFO, Fever's jumps and Lunaro's echo always follow it, and the score player can too. Internal runs at the BPM you set or tap; Start resets to bar 1. External locks to incoming MIDI clock, Start, Stop, Continue and Song Position from the Clock from input. To run a drum machine alongside, take the clock from it and the notes from your keyboard, or leave Ignore channel 10 on so its drum hits never reach the singers. Inside Claude's viewer the browser blocks MIDI devices, so use the standalone copy in Chrome or Edge for hardware; the internal clock works everywhere. Computer keys: A to ; play C to the E an octave and a half up, Z and X shift octave, and the S shortcut is off while they're on.
What you are hearing: formant synthesis running in your browser. Each singer is a three-voice section of glottal-pulse oscillators, with breath, jitter and shimmer, through five vowel filters tuned from classic soprano, alto, tenor and bass formant tables, plus their own vibrato and one elemental effect you can dial in on the strips: Kindle drive for Marzia, Breath chorus for Jovina, Tide echo for Lunaro and Root sub-octave for Saturnino. The finished plugin would add sung lyrics through trained voicebanks.
Character bios
The choir
Laid out as they sit on the square: the hot singers on the left, the cold on the right, the dry on top and the moist below. Each face follows the old humoral physiognomy, where complexion, build and expression were read as signs of temperament.
Marzia
the Kindled
Soprano · Fire · Choleric
Top left
Range
C4–C6
Humour
Yellow bile, ruled from the gall bladder
Qualities
Hot and dry
Season
Summer, noon
Planet
Mars
Age
Youth
FaceEarly twenties. A lean face with a narrow jaw, sharp chin and warm golden-tan skin, the hot and dry look the old physiognomists gave the choleric. Amber eyes with a winged lash line under thick, level brows, holding a hard stare. Red hair pulled into a high ponytail that burns to gold at the tips like a flame. Gold hoop earrings and an orange ribbed collar on a crimson jacket.
VoiceBright and forward on an open "ah". Hard attack, fast and wide vibrato. She sits at the top of the mix and does not wait her turn.
EffectKindle: tube-style saturation that heats up as her share of the square grows.
Marzia sings like she is in an argument and winning it. She will take a line up an octave just to see who follows. Use her for hooks, leads and the last chorus.
Saturnino
the Grave
Bass · Earth · Melancholic
Top right
Range
E2–E4
Humour
Black bile, ruled from the spleen
Qualities
Cold and dry
Season
Autumn, evening
Planet
Saturn
Age
Maturity
FaceForties. A long face with hollow cheeks, deep lines, dark brown skin and a short goatee, the cold and dry melancholic type. Deep-set violet eyes under heavy brows hold a tired, steady frown. Long black hair with a grey streak at the front and violet-dyed ends. A planet earring, a round gold pendant on a fine chain, a grey turtleneck and a high-collared black coat.
VoiceDark and covered on "oo". Slow onset and a slight drift in pitch, like a lamp that won't quite hold still.
EffectRoot: a sub-octave voice under every note he sings.
The scholar of the group, carrying the temperament Renaissance writers gave to poets and thinkers. He holds the floor of the harmony and gives the whole choir its weight. Drones, processionals, and the bottom of every chord.
Jovina
the Merry
Alto · Air · Sanguine
Bottom left
Range
F3–F5
Humour
Blood, ruled from the heart
Qualities
Hot and moist
Season
Spring, morning
Planet
Jupiter, the root of "jovial"
Age
Childhood
FaceAround thirty. A round face with a strong rosy flush and freckles, the sanguine picture of good blood. Her laugh squeezes her eyes shut into crescents. Curly rose-red hair with blunt bangs and a curl on top that won't lie flat, a white feather clip, gold "4" earrings for Jupiter, a cream cable-knit sweater and a coral scarf. She's caught mid-wave.
VoiceWarm and open on "eh". Soft attack, easy medium vibrato. You can hear her smiling.
EffectBreath: a shimmering chorus that spreads her across the stereo field.
The social one. She harmonizes with anybody, fills the middle of the chord, and makes everyone around her sound friendlier. Pads, backing stacks and call-and-response.
Lunaro
the Tidal
Tenor · Water · Phlegmatic
Bottom right
Range
C3–C5
Humour
Phlegm, ruled from the brain
Qualities
Cold and moist
Season
Winter, night
Planet
The Moon
Age
Old age
FaceThirties. A soft, pale face with a gentle jaw and a faint flush, the cold and moist phlegmatic. Heavy-lidded aqua eyes, teal brows and an easy closed-mouth smile. Very long silver hair that fades to aqua at the ends like water, a crescent-moon clip with a teal drop charm, and a deep-teal sweater.
VoiceSmooth and rounded on "oh". Slow swell, gentle slow vibrato, long legato glides between notes.
EffectTide: a dark feedback echo that keeps washing in after he stops.
Never in a hurry and never rattled. He slides between notes as if wading through them. Ambient beds, slow choirs, and anything that should feel like the room is underwater.
UI sketch
The full plugin window
The prototype above is the centre panel. Here is everything around it.
Header. Preset browser and voice mode. Solo crossfades one singer at a time, Choir sings all four parts at once, Duet pairs two singers across one axis of the square.
Choir strips. Each singer's level, mute and solo, octave, and their elemental effect knob: Kindle, Breath, Tide or Root.
Humour square. The main pad. The four faces react to their share of the blend the way the Delay Lama monk did, and the dashed line shows the Humour LFO's path when it's running.
Vowel morph. A–E–I–O–U strip, fully automatable. Or lock each singer to their signature vowel.
Lyric lane. Phase two. Type syllables and the choir sings them, using singing-synthesis voicebanks you build and own.
Expression. Vibrato rate and depth, glide, breath noise and formant shift. Each one defaults to the active temperament's settings.
Humour LFO. An LFO that moves the puck for you. Year orbits spring, summer, autumn and winter. Day & Night traces a figure eight. Fever wanders at random. All synced to host tempo.
Voicer. Play any chord over MIDI and it gets spread across the four parts, kept inside each singer's range.
Quintessence. One macro that pulls the blend toward the centre and fades in a fifth "ether" layer above the choir.
