Trap is written at 140 and felt at 70. The snare waits until beat three, the hats do all the moving, and the 808 slides between notes instead of restriking them. Those three things plus restraint are the genre. The grid below is programmed exactly that way - click the hat row twice on any step to turn it into a roll.
Kick syncopated and doubled, snare alone on step 9, hats on sixteenths with two rolls, and an 808 that glides into each note. Mute the hats and hear how empty trap really is - the space is not a mistake, it is the room the 808 needs.
Get these five right and the beat is trap even before you add a melody.
The grid runs at 130–150 BPM but the backbeat only lands once per bar, so it moves like a 70 BPM beat with twice the resolution. Everything else follows from that double meaning - including why the hats can be so busy without the track sounding fast.
Step 9 of 16, and nowhere else. No answer on beat one, no fill crowding it. The isolation is what gives trap its weight; adding a second snare halves the impact of the first.
Straight sixteenths, then rolls: three hits inside one step for a 1/32 triplet, six for a stutter. Vary the volume across the roll so it accelerates rather than stuttering flatly, and leave whole beats empty so the rolls mean something.
The defining sound. One long sine with a pitch slide into each new note rather than a fresh attack - the demo above does exactly that. Tune it to the key of the melody or the whole track fights itself.
They occupy the same frequency range, so either the kick is a short click on top of the 808 or the 808 ducks under the kick. Choosing one is mixing; leaving both loud is the most common reason a home trap beat sounds muddy on a car system.
Two bars of near-nothing, then a roll that leads into the turnaround. Trap is an arrangement of holes - the details land because there is somewhere for them to land.
Three genres that share a toolkit and disagree about the details.
| Trap | Drill | Boom bap | |
|---|---|---|---|
| Tempo | 130–150, half-time feel | 138–145, half-time feel | 88–94, straight |
| Kick | Syncopated, doubled | Sliding, often off-grid entirely | 1 and the "and" of 3 |
| Backbeat | Snare on beat 3 | Snare on 3, plus a ghost before it | Snare on 2 and 4 |
| Hats | Sixteenths with 1/32 rolls | Sparse, triplet-heavy | Swung eighths |
| Low end | Gliding 808, long decay | Sliding 808 with heavy portamento | Short bass note |
| Swing | 0–8 % | 0 %, the slides carry it | 15–25 % |
| Where to build it | Trap Machine Pro | DrumPad | Hip-hop beat maker → |
One hit, alone, in the middle of the bar. Loop it with nothing else for a few passes so you feel the half-time before you start filling it.
Place the 808 notes first - they are the melody of the low end - then put kicks where they reinforce the attack. Doing it the other way round is how the two end up fighting.
Straight hats first so you can hear the pulse, then convert exactly two steps into rolls: one mid-bar, one leading into the turnaround. Two is usually enough.
Mute a hat bar, drop the 808 for two beats before the drop, leave the snare naked somewhere. Trap beats get better by subtraction more often than by addition.
Program in the first, design the 808 in the third, arrange in the second.
Trap needs very few things done very well: a tuned 808, hats you can subdivide freely, and a snare that hits hard on its own. That is a small requirement list, and it is exactly the part a browser studio does without compromise - the sub is a synthesised sine with a pitch envelope, the rolls are a scheduling question, and the snare is a sample. Nothing in the genre depends on hosting a €200 plugin.
The most common mistake in home trap production is an 808 that is not in the key of the track. It sounds like a mix problem - the low end wobbles, the beat feels unstable - but it is a tuning problem. Find the root note of your melody, tune the 808 to it, and write the bassline in that scale. Quantum Synthesizer X is a good place to build one from scratch if you want control over the glide time and the decay.
A roll is three, four or six hits inside a single sixteenth step. Two things stop it sounding like a glitch: a volume ramp across the hits, so it accelerates into the next beat, and restraint about where you put it. A pattern with two well-placed rolls reads as produced; a pattern with a roll every bar reads as a demo of the roll feature. The hat row in the grid above has two, deliberately.
If you want the general theory instead of the genre, the beat-making hub breaks down the five decisions behind any pattern, and the hip-hop page covers the swung, sampled end of the same family.
They are written at 130–150 BPM, most often 140, but felt at half that speed because the snare only lands once per bar. That is why a 140 BPM trap beat feels slower than a 120 BPM house track.
A roll is several hits inside one sixteenth step - three for a triplet feel, six for a stutter. In the grid on this page, click a hat step twice to turn it into a roll. Ramp the volume across the hits so it accelerates into the next beat.
Use one continuous sine or triangle voice and glide its pitch into each new note instead of retriggering it. The demo above does this on every 808 step; Trap Machine Pro and Quantum both give you control over the glide time.
Only if one of them gets out of the way. Either use a short clicky kick layered on top of the 808, or duck the 808 under the kick. Two full-range low sounds at once is the usual cause of a muddy trap mix.
On beat 3 - step 9 of a 16-step bar - and generally nowhere else. Keeping it alone is what makes the half-time feel work.
The grid on this page is free, needs no account and lets you rewrite every track. Trap Machine Pro and the rest of the studio come with the subscription - €9.90/month with a 7-day free trial, no card.
How a beat is actually built - the grid, the swing, the genre. Play the pattern on the page, then open the full machine.
The anatomy of a beat: kick, snare, hats, swing and arrangement, on a grid you can click.
Read it → GuideBoom bap: 88 BPM, swung hats, a snare that lands late and a bass that breathes.
Read it → GuideSliding 808s, triplet hats and a snare that refuses to land where you expect it.
Read it → GuideHeavy swing, a dusty filter and a kit that sits behind the beat instead of on it.
Read it → GuideMemphis cowbell, distorted 808s and a mix that is supposed to be too loud.
Read it → GuideFour to the floor, offbeat hats, and why the clap lands a hair late on purpose.
Read it →Trap Machine Pro, DrumPad, Quantum for 808 design and 5000 samples to build kits from. €9.90/month, seven days free, no card.
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