Mix audio tracks together

Mixing is not joining

The audio joiner puts tracks end to end: file two starts when file one finishes. A mixer plays them at the same time — a vocal over a beat, a voice-over under music. If you want one long file, join. If you want layers, mix.

How mixing works

1. Open audio files, or record a track with your microphone. Each becomes a track, and they all play at the same time.
2. Drag a track’s waveform, or the ‹› handle at its start, to move it earlier or later in the mix.
3. Select a track to set its volume and pan and to add effects.
4. Use solo to hear one track on its own, and the eye to leave a track out of the mix.
5. Set a fade in or out on the finished mix, press play to hear it, then export.

Placing tracks in time

Every track starts at zero when it is added. Drag its waveform, or the ‹› handle at its start, to slide it along the timeline; the start and end times beside the track name update as you drag. With the handle selected, the arrow keys move the track by 0.1 seconds, or 1 second with Shift. To place it exactly, open its details with the ⓘ button and type the time in Starts at.

Zoom with + and −, with a pinch, or with Ctrl and the scroll wheel, and press FIT to see the whole mix again. Drag the bar under the ruler to move along.

Volume, pan, solo and leaving a track out

Volume sets how loud a track is in the mix, up to 200%. Pan places it left or right in the stereo field — useful for separating two sounds that would otherwise compete for the same space.

Solo (the headphones) silences every track that is not soloed, so you can check one on its own; turn it off and the mix returns exactly as it was. The eye leaves a track out of the mix altogether: it is not heard, not exported, and if it was the longest track the export gets shorter. Solo does not bring back a track you have left out.

Effects

Each track has its own chain of effects, applied in the order you add them: Normalize, Maximise, Remove noise, Remove hum, Soften S sounds, Remove clicks, Pitch up or down by two semitones, Speed up or Slow down without changing the pitch, and Reverse. You can also upload an impulse response — a short recording of a room, hall or plate — and use it as a reverb.

Effects apply to the whole track, or hold Shift and drag across the waveform to limit them to that part; speed changes always apply to the whole track. Each effect you add shows as a chip you can remove, and as a strip under the waveform showing the audio after that step.

Auto effects measures the track — its noise, hum, harsh S sounds, clipping and peak level — and applies only what those measurements call for. If nothing needs fixing, it says so and changes nothing.

Recording a track

Recording lives at the foot of the track list. Name the take, choose whether to Clean up automatically, then press Record audio track; a clock and a level meter show while it runs. The recording goes straight into a new track, and the microphone is released as soon as you stop.

Reordering tracks

Drag a track’s grip to move it up or down the stack; a Drop here bar shows where it will land. Unlike the joiner, this changes nothing about the sound — every track still plays at its own place in time. It is there so you can group related tracks together and keep a long mix readable.

Exporting

Name the file in the Output box, then export WAV, MP3 at 192 or 320 kbps, FLAC, M4A where your browser supports it, or every format at once. If the tracks together would clip, the whole mix is turned down just enough to avoid distortion.