Drum difficulties
Generate drum Hard, Medium, and Easy from Expert
This tool automatically adds Hard, Medium, and Easy drum parts from the Expert track.
- Runs in your browser. Your chart and audio are never uploaded.
- Deterministic: the same chart produces the same three tiers every time, in any browser.
Above: each tier reduces from the higher difficulty, based on a set of rules.
Start a chart
Drop a .sng, .zip, or chart folder that has an Expert drums track and its audio files. The generated tiers are a first pass: you review them in the chart editor and decide what ships.
Drop a .sng or .zip file, or select a chart folder.
Drop a chart folder, .zip or .sng here, or click to browse
or
The rules each tier is built on
A trained model scores every note of your Expert track once per tier, from 59 numbers that describe the note and the chart around it. A fixed sequence of steps then turns those scores into the tier’s notes. The steps are arithmetic you could check by hand, and the same chart produces the same three tiers every time.
- Chord size
- How many notes are hit at the same instant, counting this one.
- Beat in the measure
- Where the note sits between one downbeat and the next.
- Grid alignment
- Whether the note lands on the eighth-note grid.
- Nearby hits
- How many other hits land within a quarter second on either side, with a chord counted once.
- Distance to the backbone
- How far the note is from the nearest kick or snare.
- Same-drum gap
- How long the note’s own drum has been quiet before it.
- Ghost marking
- Whether the hit is charted as a ghost note.
- Section type
- Whether the note falls in a verse, a chorus, a solo, or a fill.
and the rest
- Judge repeats togetherMeasures whose Expert groove is identical are grouped first. A note’s score is averaged with the same note in every repeat, so a verse groove is judged once, as a pattern.
- Keep or dropA note survives when its score clears the tier’s fixed bar. Medium and Easy then thin surviving cymbal and tom hits that land closer than 180 ms and 250 ms to a stronger kept hit.
- Move to the tier’s lanesA second trained model proposes the lane each surviving cymbal or tom lands on in the simpler tier. Kick and snare never move.
- Make repeats matchA note’s lane is then put to a group vote: every repeat of the groove weighs in, weighted by the model’s confidence, and all the repeats take the winning lane. On Hard the vote also runs on repeated patterns shorter than a measure. Notes that end up doubled on one lane are merged.