A minimal synthesiser and sequencer for iPadOS

A banner containing the Assemble app icon.

Assemble is a synthesiser and sequencer for creating musical patterns in iPadOS or macOS on Apple Silicon Macs.


Assemble's audio engine features a synthesiser with four bandlimited wavetable oscillators and two 16x-oversampled effects, including a tempo-synchronised, modulated stereo delay, and a vibrato. The parameters of each oscillator and each audio effect can be modified easily in real-time. Its bandlimited oscillators and oversampled audio effects produce a clean and rich sound with virtually no aliasing.

Assemble in use

Assemble can record its audio output to a file and optionally generate a video clip from such a recording. Assemble offers two types of audio visualisation: waveform plots, and Lissajous plots.

Video clips generated from Assemble


The synthesiser can be played by sequencing patterns of notes with Assemble's sequencer. A sequence can include as many as eight sixteen-step patterns, which can be played discretely in Pattern Mode or sequentially in Song Mode. Once a sequence is complete, it can be named and saved locally on your device. Sequences can be saved locally or recorded in real-time and shared online.


Assemble was written for the iPad, but it runs well in macOS on Apple Silicon Macs, too. In order to target the iPhone, Assemble Light pairs Assemble's underlying audio engine with a simpler and more compact UI.


Assemble's privacy statement is available here .