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Multitrack Audio Editor & Recorder

Record from your mic, import MP3, WAV, OGG or FLAC, and edit on multiple tracks with clip fades, crossfades, EQ, compressor, reverb, delay and gate. Mix down to WAV or Opus. Runs locally in your browser.

Overview

A multitrack audio editor and recorder that runs in your browser. Import MP3, WAV, OGG, M4A or FLAC files, record from a microphone into an armed track, and arrange clips on as many tracks as you need. Each track has a fader, pan, mute, solo and an effect rack, and the session mixes down to WAV, lossless FLAC or Opus. MIDI tracks, aux sends, automation and repair tools are built in. Audio is decoded, edited and saved on your device and never uploaded.

How It Works

Drop audio files onto a track lane or use Import, and each file becomes a clip at the drop point. Drag a clip to move it, drag its edges to trim, drag the small corner squares to draw fades, and press S to split at the playhead. Overlapping clips on the same track crossfade automatically. Set the BPM and time signature to snap edits to bars or beats, turn on the metronome, drag the top strip of the ruler to set a loop region, and press Space to play. To record, arm a track with its microphone button, choose an input device and a count-in, then press R.

Step-by-Step Usage Guide

  1. Import audio files or drag them onto a track lane, or arm a track to record.
  2. Arrange the clips: move, trim, split with S, and drag the corner handles to add fades.
  3. Set the BPM, time signature and snap value if you are editing music to a grid.
  4. Balance the mix with each track's fader and pan, then add EQ, compression or reverb in the Effects tab.
  5. Open the Export tab, choose WAV, FLAC or Opus, a sample rate and an optional LUFS loudness target, and export the mix or the stems.

Technical Specifications & Standards

Playback and export run through the same Web Audio graph. Every clip is an AudioBufferSourceNode feeding a gain node that carries the clip gain plus its fade curves, so a crossfade is an equal-power fade out on the earlier clip and an equal-power fade in on the later one across exactly the overlap, which keeps the level steady. Each track then passes through its inserts in order: a 3-band EQ built from BiquadFilter shelves and a peaking band, a DynamicsCompressor with make-up gain, a ConvolverNode reverb using a generated stereo impulse, a feedback delay, gain, high-pass and low-pass filters, and a noise gate written as an AudioWorklet. After the inserts come the volume fader in dB and a StereoPanner. Mixdown renders that graph in an OfflineAudioContext at 22.05 to 96 kHz, faster than real time, with up to four seconds of tail when reverb or delay is active, and writes 16-bit or 24-bit PCM or 32-bit float WAV. Opus export uses MediaRecorder, so it encodes in real time and only appears in browsers that support it. There is no MP3 encoder. Recording captures raw PCM through an AudioWorklet starting at an exact context time, so takes land at the playhead after the count-in. Waveforms come from a multi-resolution peak cache, so zooming stays quick on long files. The session, including the audio, autosaves to IndexedDB, and every edit can be undone.

Targeted Use Cases

  • Editing a podcast with separate host and guest tracks, then cutting out pauses and mistakes.
  • Recording a voice-over against a music bed and ducking the music with the fader.
  • Sketching a song idea by layering takes over a metronome at the right tempo.
  • Cleaning a noisy recording with a high-pass filter, a noise gate and a little compression.
  • Exporting per-track WAV stems in a ZIP to hand a project to a mixing engineer.
  • Trimming and crossfading a playlist of clips into one continuous mix for a video.

Notes & Gotchas

  • Wear headphones when you record or monitor the input, otherwise the speakers bleed into the microphone.
  • Leave voice processing off for music and voice-over; echo cancellation and noise suppression are tuned for calls.
  • Watch the master meter and lower the master fader if the red clip lamp lights before you export.
  • Export 24-bit WAV for anything that will be edited or mastered again, and keep Opus for sharing.
  • Use the latency compensation slider if recorded takes sound slightly late against existing tracks.

Frequently Asked Questions

Can I export MP3 or FLAC?

FLAC, yes: a lossless FLAC encoder runs in the page (16 or 24-bit, with the MD5 checksum of the samples), for the mix and for stems. MP3 export is not offered; WAV, FLAC and, where the browser supports it, Opus are.

Does it do loudness normalisation?

Yes. The meter follows ITU-R BS.1770 (K-weighting, 400 ms gated blocks) and reports integrated loudness, short-term and momentary maximum, loudness range and true peak. Export can normalise the mix to -14, -16, -23 or -24 LUFS, with a look-ahead limiter keeping peaks under -1 dBTP.

Can I change tempo without changing pitch?

Yes. The Process tab has a WSOLA time stretch (50 to 200 percent) that keeps the pitch, and a pitch shift of up to 12 semitones that keeps the length. The older speed control still changes both together, like tape.

Is my audio uploaded to a server?

No. Files are decoded by your browser's Web Audio API, recordings are captured locally, and the autosaved session is stored in this browser's IndexedDB. Nothing is sent over the network.

Will my project still be here if I close the tab?

Yes, in the same browser. The session and its audio autosave to IndexedDB a moment after each change, and the editor offers to restore it the next time you open the page. Clearing site data removes it.

Which effects can I put on a track?

Each track can stack a 3-band EQ, compressor, reverb, delay, gain, high-pass and low-pass filter a noise gate and a limiter. Effects run in the order listed, can be reordered and bypassed, and are included in the exported mix and stems.

Related tools

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  • Extract Audio from Video - Pull the audio track out of an MP4, WebM or MOV video and save it as lossless WAV (16 or 24-bit) or as compact Opus where supported. Optional mono mixdown. Decoded locally, never uploaded.
  • Voice Recorder - Record audio from your microphone with a live timer, preview playback, and download - recordings never leave your browser.
  • Online Video Editor (Timeline, Trim, Text & Music) - Edit video in your browser on a multi-track timeline: trim, split, speed, fades, filters, transitions, titles, logos and music, then export WebM or a WAV mix. Files never leave your device.
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