This page is a close look at one song, The Noose, by A Perfect Circle (Thirteenth Step, 2003).
We split the song into separate tracks (just the singing, just the bass, just the guitar chords) and turned them into computer notes.
The page walks through 4 sections of the song, and each section shows the singing, the guitar, and the bass all lined up on top of each other so you can see how the notes and the chords fit together at the same moment.
Built from the split-apart stems, the vocal and bass transcribed to MIDI with librosa pyin, chords read off the Moises audio chart. D-sharp minor at 89 BPM, nearly static, whole verses drone on a single chord. The one bright move is a Picardy third, the tonic minor turning major for the word curious, and the song ends by holding one vocal note steady while the chords slide out from under it, the same held-note-recoloring device the ixi framework calls out on Weak and Powerless. Below is the vocal-note-versus-chord-stack close reading, one section at a time.
The verse barely moves.
The bass parks on D-sharp, the tonic (weight 21.8), and holds it for whole phrases, so the harmony is a single minor chord droning at 89 beats a minute.
Over that drone the vocal does not rest on a chord tone. Its heaviest note is G-sharp, the 4th (weight 15.7), above D-sharp, the tonic (weight 9.8).
The 4th over a static minor is a suspension that never resolves, so the melody hangs unsettled above a floor that will not move.
The only relief is the phrase-end lift to G-sharp major (IV), the one chord that breaks the drone before it falls back to the tonic. On the ixi ledger this is the same trick No Surprises runs, a vocal parked above the chord tones, the harmony carrying the emotional read the melody refuses to settle into.
This is the one bright move in a dark song.
On the word curious the home chord flips from D-sharp minor to D-sharp major, a Picardy third, the minor third raised to major for a single lyric phrase before it collapses back.
The transcription catches the melody doing the same thing in the coda's curious repeats: the vocal touches G-natural, the major 3rd (weight 3.4), where every other section leans on F-sharp, the flat-3 (weight 5.2 in verse 2).
A major third inside a song built almost entirely on the minor third is a shock of light. It lands on curious, the word where the narrator softens, and it does not last. In ixi terms this is the same modal-mixture trick Radiohead uses when Colin walks the roots into a warmer chord under a fixed melody, except here the fix is inverted, the chord itself changes quality under a held vocal.
The bridge runs the same major-minor trick one chord over.
The subdominant arrives first as G-sharp minor (iv), tug you to the ground, then brightens to G-sharp major (IV), the same swap the tonic makes on curious, now happening on the fourth chord.
The vocal holds G-sharp, the 4th (weight 13.7), and F-sharp, the flat-3 (weight 10.0), through the swap, so the melody stays fixed while the chord underneath changes its own quality.
The bridge then falls through F-sharp (III) toward the tonic, setting up the descent that ends the song. This is the ixi one-pitch-many-jobs device, moved off the tonic and onto the fourth chord, the same idea Weak and Powerless runs one album over.
The song ends by letting the halo fall.
The final section rides F-sharp to C-sharp, the III to bVII, the flat-side chords, back toward D-sharp, while the vocal parks on A-sharp, the fifth (weight 10.9).
That held A-sharp recolors as the chords slide beneath it: the 3rd over F-sharp, the 6th over C-sharp, and the 5th over D-sharp.
Your halo slipping down is sung on a note that stays level while the harmony sinks under it, the falling ground doing the work the steady voice will not.
The last word, to choke you now, lands back on the static tonic, the noose pulled tight on the chord the whole song could not escape. On the ixi ledger this closes the song with the same held-pitch-shifting-jobs move Weak and Powerless opens its chorus with, one album fingerprint that Thirteenth Step keeps returning to.