The short guide
Understand the idea
Sampling means building music from existing recorded sound instead of generating every note from scratch. Synthesis makes a sound from oscillators and settings; a sample is audio that already exists, and chopping is cutting it into short slices you can rearrange. A slice has two separate parts: its source window, which says which stretch of the clip it plays, and its placement, which says on which beat it plays.
What you can explore
- Trim a slice by moving its start and end inside the clip.
- Rearrange slices across four beats and leave space with a rest.
- Reverse a single beat without changing the slice everywhere else.
A worked example
A-C-Rest-B with B flipped
The clip is cut into four regions: A is a glass bell, B a woody tick, C a shaker and D a low glass thud. Slice B is trimmed to 640 to 940 ms, so it keeps 300 ms of its region. At 120 BPM each beat lasts 500 ms, so the trimmed B leaves 200 ms of quiet before the bar repeats. Beat 4 plays B reversed; slice D stays in the source but is not used.
- Beat 1
- A, the glass bell, forwards, full 0 to 500 ms window.
- Beat 2
- C, the shaker, forwards.
- Beat 3
- Rest: 500 ms of silence.
- Beat 4
- B trimmed to 640 to 940 ms, played backwards, then 200 ms of quiet.
Where the sound comes from
Every sound in this lesson comes from one fixed clip called tp-glass-kit-v1. It is 2 seconds of mono audio at 24 kHz, synthesized by TunePal code from a fixed seed, so it is the same on every device. It is not a recording of a person, a song or an instrument, and you cannot upload your own audio here.
For your own projects, start with audio you made or a sample library that permits your intended use. This lesson uses TunePal’s original practice clip.
Source windows and beat placement
Choose a slice, then move Trim start or Trim end with the slider, the minus and plus buttons, or by typing a time. Each step is 10 ms, which is 240 samples of the clip. The waveform shows what the slice keeps and what it trims away.
Trimming changes the slice itself, so editing slice B updates every beat that plays B. Placing a slice is separate: tap a numbered beat, choose A, B, C, D or Rest, and only that beat changes. Reverse also belongs to one beat, so a reversed B on beat 4 does not flip a B on beat 1.
On the flip step, compare Forwards and Backwards for the same kept slice window. Choosing a comparison direction changes only the picture; press Hear comparison to play it. The saved reverse switch below is separate, so exploring a comparison never rewrites your pattern.
The tempo stays at 120 BPM. Slices are never stretched or pitched to fit, so a short slice simply leaves quiet before the next beat. With sound off, you can still trim, arrange and review your pattern by reading the waveform and the beat cards.
Common questions
What is the difference between sampling and synthesis?
Synthesis creates a sound from settings such as oscillators and filters. Sampling starts from audio that already exists and reshapes it by cutting, rearranging and reversing it.
What does chopping a sample mean?
Chopping is cutting a clip into short slices. Each slice keeps a start and end point in the original audio, and you choose where each slice plays in your pattern.
Why does trimming one slice change several beats?
A trim edits the slice, not a beat. Every beat that plays that slice uses the same source window. Reverse is different: it is saved per beat.
What can this lesson not do?
It does not record, upload, stretch, pitch or export audio, and the tempo is fixed. The recipe download is a text description of your slices and beats, not a sound file. Your work is kept in this browser.
Published by TunePal. Interactive examples for beginner music producers.