SequencAir

Name: SequencAir
Author: Full Bucket Music

by Full Bucket Music · Synth · Step sequencer with mono synth

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SequencAir is a free step sequencer with a built-in monophonic synthesizer, offering 16 chainable banks of 16 steps.

Each step has note, octave, velocity, gate, skip and mute plus two MIDI CC or synth parameter values; it syncs to the host and is free.

Best for: Keys & Synths, Sound Design. Genres: Electronic & EDM.

Keywords: sequencer, free, monophonic, simple, tempo-synced, classic, basses, CPU-light, resizable UI, sound design.

What it does

SequencAir is a free classic-style step sequencer with a simple mono synth built in. It can play its own synth or drive other instruments over MIDI, and the developer stresses its "extremely low CPU consumption".

Banks and steps: 16 banks of 16 steps each; CHAIN buttons play selected banks in sequence for longer lines.
Per-step control: pitch, octave, velocity, gate time, skip and mute, plus two assignable rows for MIDI CCs or synth parameters.
Play modes: Forward, Reverse, Forward-Reverse, Reverse-Forward and Random.
Timing: sync to host, a clock divider (DIV) that sets the note length per step, and swing that shifts the even steps; Skip allows odd time signatures.
MIDI control: optional start, stop and transpose by MIDI note, and MIDI output on an assignable channel to drive other plugins or hardware.
Built-in synth: the manual calls it "a very primitive synth" with one oscillator, one filter and a simple envelope; it can be switched off.
Interface: MIDI Learn for every parameter, factory presets and a resizable UI.

The current version is 1.2.1 (6 Feb 2026). It is a free download; the developer accepts donations.

Source: Full Bucket Music product page

When to use it

SequencAir is the better pick when the sequence comes first and you want a free, hardware-style step grid with per-step CC lanes. Compared with the arpeggiators in Hive 2 or Phase Plant, it gives you hand-programmed 16-step patterns, chained banks and play directions, and it can drive any other synth over MIDI. Its own synth is far simpler than Vital or Diva, so it works best as a sequencer feeding a better sound source. It is lighter on CPU than any of them.

Best for: step-sequenced basslines, acid and Berlin-school patterns, and sequencing other plugins or hardware over MIDI.
Genres: techno, acid, Berlin school, synthwave and other electronic styles.
Look elsewhere if: you want a rich synth voice; route it into Diva or Vital, or use a synth with a deeper built-in sequencer.
Tip: run the built-in synth into a delay for classic analog-style arpeggio sequences, or switch it off and send the MIDI to another instrument.

What producers say

The few reviews are positive and focus on its value as a free MIDI sequencer.

KVR users rate it 5 out of 5 from 1 review, called a "fantastic little freebie" used to send MIDI control to other devices.
Bedroom Producers Blog found the layout "very simple and intuitive" and a good starting point, and suggested pairing the synth with a delay.

Where to buy

Full Bucket Music: Free

Tutorials and reviews

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