Understanding your playlist

Attracr describes music with a handful of measurements. None of them is a score, and none of them is a target — a playlist of quiet acoustic recordings is not worse than a loud one, it is a different thing. What the numbers are good for is noticing when a track is not the thing the rest of the playlist is.

Energy

Energy is how intense and busy a recording feels. High energy sounds loud, fast and full: distorted guitars, a hard drum kit, a chorus that pushes forward. Low energy sounds sparse and unhurried — a solo piano ballad played softly sits near the bottom, a stadium rock chorus near the top.

Valence

Valence is the emotional colour of a track: bright and cheerful at the high end, dark or melancholy at the low end. It is about mood, not speed, so a fast song can still be sad. An upbeat motown single reads high; a slow minor-key torch song reads low.

Danceability

Danceability is how easy a track is to move to — steady pulse, clear beat, a rhythm you can settle into. High means the groove is regular and obvious, the way a disco or house track keeps the same footing all the way through. Low means the rhythm shifts or hides, as in a free-time folk recording with no drums at all.

Acousticness

Acousticness is how much of the sound comes from instruments and voices rather than electronics. High means air in the room: acoustic guitar, upright bass, a singer close to the microphone. Low means synthesizers, drum machines and heavily processed sound — an unplugged live take against a club remix of the same song.

Acousticness is read as a kind, not as a distance. Most recorded music is neither purely acoustic nor purely electronic, and the measurement is far surer about the two ends than about the middle, so the harmony view sorts tracks into electronic, in-between and acoustic rather than measuring how far each one sits from an average. When a playlist has no production style of its own, it says so and judges nothing.

Instrumentalness

Instrumentalness is how much of the track has no singing in it. High means a piece carries itself without a vocal line, like a film score cue or an ambient composition. Low means there are lyrics being sung. Wordless vocal textures used as an instrument sit somewhere in between, which is worth remembering before treating this one as a verdict.

Tempo

Tempo is speed, counted in beats per minute — the rate you would tap your foot at. Fast tempo drives: a punk single or a drum and bass track. Slow tempo settles: a blues shuffle or a ballad. Tempo is the measurement listeners notice fastest when a playlist changes pace mid-run.

Loudness

Loudness is the average level of the recording, which is a property of how it was mixed and mastered rather than how you play it back. Modern pop and metal are usually mastered loud and dense; jazz and classical recordings keep more room between quiet and loud moments. A playlist that mixes both makes listeners reach for the volume control.

Speechiness

Speechiness is how much of the track is spoken words rather than sung ones. High means talk: a podcast excerpt, a comedy set, a spoken-word piece. Rap sits in the middle, since it is wordy but performed to a beat, while most sung pop sits low.

Liveness

Liveness is how much the recording sounds like it happened in front of an audience — room reflections, crowd noise, a performance rather than a take. A concert album reads high, a studio recording reads low. A studio track with an artificial crowd sample can read high too, so treat it as a description of the sound, not proof of the venue.

Reading the harmony view

The harmony view plots every track in your playlist against the others, so a playlist with a clear identity shows up as a cloud with a dense middle. Tracks near the centre are the ones that sound most like the playlist as a whole. Tracks at the edge are the ones that differ most from that centre on the measurements above.

Sitting at the edge is information, not a mistake. A closing track that drops the energy on purpose, a single loud outlier that works as a jolt, a cover that belongs for reasons no measurement sees — all of those sit at the edge and all of them can be right. The view tells you which tracks stand apart; whether that is deliberate is yours to say.

Two of the measurements are read as kinds rather than distances — production style and danceability. For those the view asks whether the playlist leans one way at all, and only then points at the tracks that lean the other. A playlist that spans both is not judged.

Reading followers against changes

The follower graph shows a daily count. The change history shows the days tracks were added or removed. Put them on the same timeline and you can see what happened after an edit, which is the part of the picture you actually control.

Read it as correlation, because that is all it is. Followers move for reasons Attracr cannot see — an editorial placement, an artist sharing a link, a season, a song that got popular elsewhere. A change that lines up with a rise is worth noticing, and it tends to mean more once the same kind of edit lines up with the same kind of move more than once. One coincidence is a coincidence.

Attracr terms

Harmony score

A single figure for how consistent a playlist sounds — how closely its tracks agree with each other on energy, mood, tempo and the rest. A high harmony score means a recognisable sound. A low one means variety, which is a fair choice for a mixtape and a problem for a playlist meant to hold one mood.

Outlier

A track that sits far from the rest of the playlist on several measurements at once. Attracr flags it so you can look at it. Keeping it is a perfectly good answer.

Candidate

A track Attracr thinks is worth adding to a playlist, because it sounds like what is already there. Candidates are suggestions; you add them in Spotify, or mark them as not a fit.

Removal candidate

A track already in the playlist that is worth a second look, picked on how long it has been there and how close it sits to being an outlier. It is a nudge to keep the playlist fresh, not a verdict.

Core track

A track that defines the playlist, its character and its identity. Core tracks are there to stay: Attracr never suggests removing one, however long it has been there. A core track can also be core for one year only, after which it drops out of the core by itself.