Hover over any underlined word in the report (or tap it on a phone) and it'll explain itself. Here they all are in one place.

The basics

• Length — How long the track runs, in minutes and seconds.
• Tempo — How fast the beat goes, in beats per minute (BPM). 60 is one beat a second. Ballads tend to sit around 60-80, pop around 90-130 and dance music around 120-130. Now and then we'll read half or double the speed you feel.
• Meter — How the beats group into bars. 4/4 means four beats a bar (most pop, rock and blues), 3/4 means three (that waltz sway), and 5/4 or 7/4 are odd meters you'll hear in prog, jazz and film music. 'Assumed' means the evidence was thin, so we went with the most common one, 4/4.
• Bar — One full cycle of the meter, like four beats in 4/4. We count chord changes, sections and riffs in bars.
• Key — The home note and scale the music keeps coming back to, like E major. Major usually sounds brighter, minor darker.
• Camelot — A code DJs and producers use for keys: numbers 1-12 round a wheel, A for minor and B for major. Tracks with the same code, a number either side (same letter), or the same number with the other letter mix together smoothly.
• Mode — The flavour of the scale: which notes surround the home note. Hover over a mode's name to see what it feels like.
• Note names — A letter plus an octave number. C4 is middle C and A4 is 440 Hz. A bass guitar's lowest string is E1 and a guitar's is E2. # means a semitone up (sharp), b a semitone down (flat).

Harmony

• Confidence — How well the notes fit the key, from 0 to 1. Above 0.75 is clear. Below 0.6 the harmony is ambiguous, which is common with modal music, drones and power chords.
• Runner-up — The next most likely key. It's often the 'relative' key (C major and A minor share the same notes), which is why the two are easy to mix up.
• Mode confidence — How clearly one mode beats the others. 'Low' means another mode fits almost as well, usually because the note that would settle it hardly gets played.
• Colour note — The note that gives this mode its character. Lean on it in a melody and the mode comes through clearly.
• Scale — The seven notes of the key's mode, starting from the home note.
• Chord names — C is C major and Cm is C minor. C7 is a dominant 7th (bluesy, and it wants to move to the chord a 4th up), Cm7 a minor 7th (soft and jazzy), Cmaj7 a major 7th (dreamy). C5 is a power chord: just the root and 5th, neither major nor minor, the bread and butter of rock and blues guitar.
• Slash chord — A/E means an A chord with E as the lowest (bass) note.
• Capo — A clamp across the guitar neck that raises every string by the fret it sits on, so easy open chord shapes sound higher. Fingerings are written from the low E string to the high E string: a number is the fret to press, 0 an open string, x a string you don't play. Chords played as power chords (C5, D5) aren't counted: that shape moves anywhere on the neck.
• Chord root — The note a chord is named after, like D in D7. Bass lines often play it.
• Roman numerals — Chords named by where they sit in the key. I is the home chord, and IV and V are built on the 4th and 5th notes. Upper case is major, lower case minor, so 'i - iv - V' describes the same progression in any key.
• AABA — The 32-bar song form behind jazz standards and classic pop: an 8-bar A section played twice, a contrasting 8-bar B section (the bridge, or 'middle eight'), then A once more. We spot it by comparing the chords of 8-bar stretches.
• Chord loop — A short run of chords that repeats, like the four chords under a verse. We look for loops within each key and show them starting on the home chord.
• Chord timeline — Every chord change in order, with the time it starts. Names like A/E show the bass note when it isn't the chord's root. A ? means that chord's notes were no louder than the other notes sounding at the time, as in a fast run or a lick, so the name is a best guess.
• Harmonic rhythm — How often the chord changes.
• Time in each key — How long the music stays in each key. Songs often move to a new key (modulate) for a chorus or a bridge.
• Key timeline — The keys in the order they come, with their start and end times.
• Drone / pedal — A note that keeps sounding while the chords change above it.
• Tuning — How far the instrument sits from standard pitch (A = 440 Hz), in cents. 100 cents is one semitone.
• Major/minor blur — The major and the minor 3rd both stand out. You hear this a lot in blues and rock, where the minor 3rd is a 'blue note' played over major chords.

Form

• Form — The order of the song's sections. Each letter is a section, and a letter that comes back sounds like the earlier one (A B A C could be verse, chorus, verse, bridge). We work this out automatically, so treat it as a rough map.
• Section energy — Low, medium or high: how loud the section is compared with the track as a whole.
• Instrument columns — ✓ means that instrument clearly plays in the section. — means it doesn't, or it's too quiet for us to tell.

Energy & mood

• Energy — How loud the track is from start (left) to end (right), in 24 slices. Taller bars are louder, so you can spot builds, drops and breakdowns at a glance.
• Energy level — How intense a section feels, from 1 to 10. We work it out from how loud it is (compared with the loudest section), how many notes or hits there are each second, how bright it sounds, and the tempo.
• Mood — Where the music sits between dark and bright, as positivity from 0 to 100. We base it on the mode, how much of the time minor chords play, brightness and tempo. Put together with energy, that gives words like 'calm', 'driving' or 'melancholic'. It's a rule of thumb, not a verdict: how you play shapes the feel too.
• Positivity — 0 is dark or sad, 100 bright or happy. We estimate it from the mode, minor chords, brightness and tempo.
• Loudness vs peak — How much quieter the section is than the loudest one, in dB. 0 is the loudest, and -6 dB sounds about half as loud.
• Notes per second — How many notes or hits start each second. It's a measure of how busy the playing is.
• Brightness — The 'centre of gravity' of the sound, in Hz. Higher sounds brighter or harsher (cymbals, distortion), lower sounds darker or warmer.
• Minor chords — How much of the section's time minor chords take up. More minor usually feels darker.

Instruments

• Who plays when — One row per instrument, one block per section: filled where it plays (stronger = surer), a dashed outline where it might (drums we couldn't confirm), faint where it doesn't. The vocals come from a trained model listening second by second; the drums, bass and chords from our own measurements (or, with Demucs, from each separated part). Hover over a block for the evidence.
• Separation — We pull the drums apart from everything else before we analyse anything. Demucs, an AI model, does this well. Without it we use a simpler split by sound type: sharp hits versus held notes.
• Drum grid — One bar cut into 16 sixteenth-notes (1 e & a 2 e & a 3 e & a 4 e & a). K is a kick-heavy hit, S a snare-heavy hit, X a strong hit (kick and snare), x a lighter hit, and . means there's usually nothing. h is a hi-hat or cymbal.
• Groove repetition — How closely each bar sticks to the main drum groove. Tight feels like a loop, loose means plenty of variation.
• Groove traits — A backbeat puts the snare on beats 2 and 4 (rock and pop). Four-on-the-floor puts the kick on every beat (disco and house). Half-time puts the snare only on beat 3, so it feels slower.
• Fill — A short break from the main groove, usually leading into a new section.
• Bass style — Roots means mostly the chords' root notes. Pedal holds one note under changing chords. Riff is a repeating figure. Walking is a note on every beat, moving step by step, as in jazz.
• Clear notes — The share of beats where we could hear a clear bass pitch. Rests, quiet notes and muddy notes don't count.
• Lowest part — When there's no separate bass instrument, we take the lowest notes of the main instrument (say, a guitarist's thumb on the low strings) and analyse them like a bass line.
• Sheet music — The bass notes we found in the recording, placed on a 16th-note grid in bars of the detected meter, with the chords written above. It's automatic, so check it by ear. Swing and triplets get rounded to the nearest 16th.
• Note lengths — A whole note is 4 beats, a half note 2, a quarter note 1, an 8th half a beat and a 16th a quarter of a beat. A dot makes a note half as long again.
• Rhythm grid — One bar in 16ths (1 e & a 2 e & a ...). x or X marks where a note starts: X in most bars, x in some, . rarely.

Rhythm & sound

• Pulse — How steady the tempo is: locked to a click, played by feel, loose, or free with no fixed beat.
• Syncopation — Hits that land between the beats rather than on them. It's what makes a groove feel pushed or funky.
• Percussive — How much of the sound's energy comes from sharp attacks (drums, but also picked or strummed notes) rather than held notes.
• Tone — Dark and warm, balanced, or bright, going by the brightness in Hz. Clean or noisy tells you how pitched or how noise-like the sound is.
• dBFS — Loudness measured against the digital maximum (0 dBFS). The more negative, the quieter.
• LUFS — Loudness as ears hear it (ITU-R BS.1770, the standard streaming services use): low bass counts for less, the 2-4 kHz range for more, and silent moments are left out. Spotify plays music at about -14 LUFS, turning louder tracks down.
• True peak — The highest level the waveform reaches, including between the samples, where a converter or an mp3/AAC encoder can overshoot. Above 0 dBTP the sound clips; Spotify asks for -1 dBTP or lower.
• Loudness range — How much the level moves between the quieter and louder passages, in LU (EBU Tech 3342: the spread from the 10th to the 95th percentile of 3-second loudness). Small means even and compressed, large means dynamic.
• Stereo correlation — How similar the left and right channels are: +1 is mono, values between 0 and +1 are normal for a stereo mix (lower = wider), and below 0 means parts are out of phase and cancel on a mono speaker.
• Dynamic range — The gap between the loud and quiet parts, in dB. Bigger means more contrast.
• Frequency balance — How the energy spreads across the range: sub (felt more than heard), bass, low-mids (body), high-mids (presence) and air (sparkle).

Instruments we hear

• Instruments we hear — A trained model's opinion of which instruments play (Essentia's instrument model, MTG-UPF, 40 instruments), with how sure it is. It's a second opinion next to our own measurements and what you tick: shown and compared, never used to change a result.

Producer's view

• Sidechain — Pumping: the pads, chords and synths duck right after each kick and swell back before the next, usually from a compressor triggered by the kick. Gentle is 3-6 dB, heavy (the obvious French-house 'breathing') more than 6.
• Drop — In dance music, the moment the full beat and bass come back in after a breakdown or build. We map each section's role (intro, build, drop, breakdown, outro), its length in bars, and how far the drop jumps in level above what leads into it.
• Mono low end — Club systems and phone speakers play the bass in mono, so a wide or out-of-phase low end partly cancels on them. Correlation below 120 Hz near +1 is mono and safe; below 0.6 is wide.
• PLR — Peak-to-loudness ratio: true peak minus loudness (LUFS). Below about 8 dB a master is heavily limited (dense, loud, little punch); 8-11 is typical of modern club and pop masters; above that it's dynamic.

Melody

• Scale degree — A note's place in the key: 1 is the home note, 5 the fifth above it, b6 a flattened sixth, and so on. Degrees describe a melody whatever key it's in.
• Melody shape — The overall contour (rising, falling, arch or wave), plus its range and how much it moves by step to the next note versus leaping.
• Intervals — The distance from each note to the next: half-step, whole-step, 3rds, 4ths, 5ths and so on. Small steps sound smooth and singable, big leaps dramatic.
• Top line — The loudest pitched part, picked out automatically. On a full-band phone recording it's often the chord instrument rather than the melody.
• Variations — Classic ways to develop a short idea. Inversion flips its intervals upside down, retrograde plays it backwards, a sequence repeats it a step higher, and an answer phrase brings it home to the home note.

Ideas & files

• Shared DNA — Building blocks (chord loops, scale, groove, form, melodic tricks) your track has in common with well-known recordings. They're there for study and inspiration, not to say it 'sounds like' anything.
• AI brainstorm — Written by an AI language model that reads the analysis numbers, never your audio. Treat it like a sparring partner: we check any times and chords it names, but its opinions are its own.
• MIDI — A file of notes rather than sound. Drag it into a DAW (GarageBand, Logic, Ableton, FL Studio and so on) or MuseScore, pick any instrument, then edit, transpose or loop it.
• MusicXML — The standard file format for sheet music. It opens in MuseScore (free), Sibelius, Dorico, Finale and many DAWs, where you can read it, play it back and edit it.
• Report file — This whole report as a text file (Markdown, .md). It opens in any text editor or notes app and shows up formatted on GitHub, Notion or Obsidian.
• Data file — Every number behind the report, in a file programs can read (JSON). Handy for spreadsheets, your own scripts or another tool.

Modes

• Ionian (major) — The ordinary major scale: bright, stable, resolved.
• Lydian — Major with a raised 4th: dreamy, floating, film-score.
• Mixolydian — Major with a flat 7th: bluesy, rock, folk, laid-back.
• Phrygian dominant — Flat 2nd with a major 3rd: Spanish / flamenco / Middle-Eastern.
• Dorian — Minor with a raised 6th: soulful, jazzy, funky, less sad than plain minor.
• Aeolian (natural minor) — The ordinary minor scale: sad, serious, emotional.
• Harmonic minor — Minor with a raised 7th: dramatic, classical, exotic pull to home.
• Phrygian — Minor with a flat 2nd: dark, tense, metal / cinematic.