Rhythm Atlas · 8 of 10
Rhythm Atlas · Lesson 8 of 10
Trance: Four-Floor at 138
Four kicks and a question mark. The floor is verified; the clap everyone assumes is masked inside the kick’s onsets — present by every account except the measurement’s. This lesson teaches both the grid and the difference.
Waveform — the verified four-floor, rendered in the lab at 138
Measured — tempo of the four-floor master
137.8 BPM
Against a claim of 138. Nobody will ever hear 0.2 BPM — but a catalog that checks the small numbers can be trusted on the big ones. That’s the whole business model of this page.
Step 1
138 on the poster, 137.8 in the audio
Trance’s skeleton is the house floor at full stretch: kick on 1, 5, 9, 13, nothing else certified. The tempo tells the atlas’s usual story in miniature — the source claims 138 BPM, and the audio measures 137.8. A fifth of a BPM is inaudible; the habit of checking is not.
Step 2
What "masked" means, and why we still show the row
A masked hit is one that’s probably there — the arrangement says so, the genre says so — but the kick on the same step is loud enough that the measurement can’t separate the two. We show the clap row hatched rather than deleting it, because the honest state of knowledge is "claimed, not verified," and a hatched row teaches that better than either a solid row or a missing one.
The clap row is hatched: the source material places claps at 5 and 13, but in the audio they sit inside the kick’s own onsets — masked — so the row is claimed, not verified. The hat and arpeggio rows would not resolve at all and aren’t drawn.
Step 3
Program the floor; earn the rest by ear
Load the floor into the Beat Maker and it will feel unfinished — that’s the point of this lesson’s skeleton. The drive in trance comes from what rides the floor: offbeat bass, the arp, the hats. Those rows are your arrangement work. The atlas certifies the floor your work stands on.
Try it in the browser — free, nothing to install
Beat MakerThis grid, loaded for you — the four-floor at 138 BPM on the site sequencer, free packs’ soundsPattern PlayerThe free MIDI patterns in three voices — the Listen tabCheck your work
Failure checkCommon failure: transcribing what must be there
Filling in the clap, hats and arp from genre habit produces a tidy grid that describes no actual record. When a hit is masked, the professional move is to say so — in a transcription, in a mix report, in a pack’s contents list. Certainty you haven’t earned is just decoration.
The floor, shipped
No trance pack sits in our catalog. The closest foundation is the same one the house lesson stands on — GOLDEN HOUR for the floor’s warm side — and the free sounds in the Beat Maker below are the Free Drum One-Shots. Program the floor at 138 and build upward.
Keep learning
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Blues: The Triplet Shuffle
Every grid so far divided the beat in two or four. Blues divides it in three.
Next lessonRhythm Atlas · Previous
House: Four-Floor and the Clap
The same floor at house tempo, with both rows verified.
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