Chopping a sample

What chopping is for

Chopping means slicing a recording into smaller segments so you can rearrange and play them in a new sequence. Each segment can go on its own pad, so one recording can become a whole kit.

Custom slicing

Put a sound on a pad, then open Chop to see its waveform. The Chopper starts in Custom, where you mark every slice yourself. Tap two points on the waveform to select, drag the handles to adjust the start and end, then press + Add to save the slice. Clear drops the selection without touching anything saved. Saved slices go into a named list and show on the waveform, so you can come back to them: tap one, or step through them with ‹ and ›. The list belongs to the sample, not the pad, so two pads with the same sound share it.

You can play, rename and delete saved slices from each one's ⋮ menu, and send any of them to any pad in any bank with its → Pad. The waveform zooms, so even a very short slice is easy to select. Pinch it with two fingers, or pinch a trackpad, to zoom in on the spot you are touching.

Three faster ways to slice

Along the bottom of the slice list are three modes that place the slices for you: Auto divides the sample into equal parts, Detect finds where each sound starts, and Lazy lets you tap the slices in time with the music. Each panel has an i that explains it.

Only one mode is on at a time. Press the one that is on, or tap outside its panel, to close it and go back to Custom, where your selection and saved slices are as you left them. While a mode is on, step through its slices with ‹ and ›: each step selects the next slice, plays it and scrolls it into view, which helps when the slices are too thin to tap. Press + Add to keep the one you are on in your list, or Split to send them all to a bank.

Auto

Auto divides the sample into equal parts. Pick how many, or fine-tune the number with − and +, and the divisions appear on the waveform. Drag any division to adjust it. Adjusting does not add anything to your saved list, so you can fine-tune the divisions before keeping any of them. Auto starts fresh each time you open it, since it is quick to set up again.

Detect

Detect slices where each sound starts, such as each kick, snare or note, instead of into equal parts. It suits drum breaks and loops, where equal parts land between hits. The panel shows how many slices it found, roughly how long each one is, and whether they fit on a bank.

Sensitivity sets how quiet a sound can be and still get its own slice, from the loudest hits only up to every ghost note. Detect often finds more slices than a bank has pads, so keep the ones you want with + Add and send each with its → Pad. When it finds sixteen or fewer, Split sends them all to a bank at once. Like Auto, Detect starts fresh each time you open it.

Lazy

Lazy slices in time with the music, the way lazy chop works on an MPC. Press Play and tap Tap on each sound you want a slice to start on. Each slice runs from one tap to the next, and the last runs to the end of the sample. On a computer the space bar taps too.

Snap to hits moves each tap to the nearest sound start, so a tap that lands a little late still lands on the drum. Play again to tap more slices in among the ones you have, or press Clear to start over. Your taps stay until you clear them, even when you close Lazy.

Split

Split places the slices on the waveform across a whole bank in one action, one per pad, in order. It is the fastest way to turn a loaded sample into playable pads.

Split is at the bottom of the Auto, Detect and Lazy panels, beside + Add, and sends exactly the slices on the waveform, including any you have dragged. Eight slices fill eight pads and leave the rest empty. A bank has sixteen pads, so Split is unavailable above sixteen slices.

If the current bank is empty, Split fills it. Otherwise it fills the first empty bank, so the kit you are working on is left alone.

Stems

Stems separates a sample into four parts, drums, bass, vocals and everything else, each a sound of its own. Select part of the waveform to split just that, or leave nothing selected to split the whole sample, then press Split into stems. When it finishes, the four stems appear as lanes: tap one to hear it, send it to a pad with its → Pad, or press Split to Bank to put all four on a bank.

The splitting runs on your own device, using its graphics chip through WebGPU. That works in Chrome or Edge on a computer and in Safari on a recent iPhone. On iOS 18, turn it on first in Settings › Apps › Safari › Advanced › Feature Flags › WebGPU. The first split downloads a 126MB model, which is kept for next time. A split takes a while, so you can close the panel and keep working while it runs.

Finished stems are saved in your browser, so a sample is only split once and its stems are there when you come back to it, even after a reload. The panel's ⋮ menu clears the stems of this sample, removes every saved stem, or removes the model to free its space. Stems is part of Pro.

Overriding a pad

Each saved slice has a ⋮ menu with Rename, Lock, Delete and Override pad. Overriding cuts the pad you are on down to just that slice, keeping its colour and effects, instead of sending the slice to a new pad. The rest of the sample is gone, so it asks first, and it cannot be undone.

To start the list over, the ⋮ at the left end of the modes has Delete all chops, which removes every saved slice of this sample after asking first. Pads you have already sent slices to keep their sound.