Audio
Sound is a first-class part of the timeline: every audio layer, and every video layer’s own track, is mixed by the engine and follows the same clip bars as the picture.
Importing
Audio… in the toolbar’s New Layer menu opens a file picker, or drag a
file in. On the cloud path, audio is stored as resource_type: 'video' in
Cloudinary — an implementation detail that only matters if you are looking at
raw asset keys.
The Sound FX section of the Library panel holds 18 bundled sounds; drag them straight onto the timeline.
The Audio panel
Window ▸ Audio or Ctrl/⌘ + 4. It is a mixer rather than only a meter:
- a VU with clipping indicators and peak hold;
- two faders that change the selected layer’s Level and Pan — not another global control;
- units in decibels or percent, and a slider minimum, as After Effects has.
Video layers carry their own track
A video layer is a voice, not just a picture. Its audio plays in the viewport and is exported with it, scheduled off the same clip bars as the picture. That is what makes trim, split, slip and delete carry the sound structurally: there is nothing to keep in sync, because there is only one bar.
Solo covers audio, on both layer kinds. Soloing a title does not leave the footage audible.
When a clip’s picture is retimed — Time Stretch, reverse, Time Remap or a Speed change — its audio follows the retimed picture in constant-rate segments rather than staying at the original speed.
The audio layer
The Audio settings section of the Properties panel carries:
| Control | Notes |
|---|---|
| Waveform | The decoded waveform, with a playhead marker |
| Level | Volume, in dB. Has a stopwatch like any other property |
| Pan | Has a stopwatch too |
| In / out trim | Within the source |
| Mute | — |
Level and Pan are keyframable from anywhere
Audio properties sample per frame, like every other animatable property. Set a keyframe on Level or Pan in the inspector, the timeline or the Audio panel and you get a real fade or a real pan. Layers made before Level had a stopwatch keep the exact loudness they had.
Levels are stored in dB. Projects that stored the old percentage are migrated, so
100 stays unity rather than becoming +100 dB.
The audio expression accessor — currentLevel(), which drives Audio Throb —
counts audio layers only, deliberately. Including footage would silently
re-key every existing audio-reactive project the moment a clip was added. The
VU meter is unaffected: it meters the master bus, which does include footage.
Fades, gate and ducking
These live under Animation ▸ Audio. Fades, the gate and ducking write ordinary level keyframes you can reshape afterwards.
| Command | What it does |
|---|---|
| Fade In / Fade Out | One click each. They leave an existing duck alone |
| Noise Gate… | Pulls a layer down wherever it is quieter than a threshold — room tone between phrases, hiss under a take |
| Duck Under Voice… | Lowers music under speech |
| Remove Silence… | Cuts out the quiet parts |
| Markers on Beats / Animate In on Beats | Beat-driven verbs, using the composition’s sound |
| Convert Audio to Keyframes | Bakes the audio’s amplitude into keyframes |
The gate is a baked verb rather than a live effect: the result is level keyframes, so you can see where the gate closed, drag a point that closed too early and keep the rest. The cost is that the bake goes stale if the source changes, so the settings are remembered and you can re-run it.
Layer switches and keys
- A speaker switch on every layer in the timeline, beside the eye, shows and toggles that layer’s audio mute. It is separate from the visibility eye, which hides the picture, and it writes the same property as the inspector’s Mute switch — one piece of state, seen twice.
- Alt-click a solo switch to solo just that layer.
- L shows a layer’s audio levels; L L shows its waveform — both on the same time axis as the keyframes above them.
- Audio-only preview: Numpad . plays the sound from the playhead in real time without drawing the picture, so a long composition auditions at true speed. Numpad * drops a marker while it plays, so you can tap along to the music.
Playback and the audio device
Space plays and pauses, and the sound follows the playhead. Audio timing belongs to the clip bar: move the layer bar and the audio moves with it. One voice per clip.
Window ▸ Customize… ▸ Audio chooses which output device previews play through, and trades latency for stability on a busy machine — a larger buffer is steadier and responds to the transport a little later. A latency change applies from the next playback.
The waveform on the clip bar
Both audio and video bars draw a waveform, from the same asset the picture comes from — so the two can never disagree about which file is shown.
The envelope is sliced to the clip’s own source window, so trimming or slipping redraws it. A bar that drew the whole file scaled to its width would look like a working waveform — peaks, silence, shape — while the peaks under the playhead were not the audio you would hear there. Cutting to a beat is what this is for, so that distinction is the whole feature.
The VU meter
Stereo peak bars in the status bar, from the master left/right analysers. It draws only while playing, and is hidden when there is no audio path. An absent VU meter therefore means “no audio path”, not “silence”. The Audio panel has the larger version.
Audio in exports
Audio is mixed by the engine and muxed into video exports by ffmpeg.
| Format | Audio |
|---|---|
| MP4 | AAC |
| WebM | Opus |
| MOV / ProRes | Yes |
| GIF | No — the format has none |
| PNG / JPEG sequence | Rides along as a separate audio.wav |
A PNG sequence export writes audio.wav alongside the frames. If you are
handing frames to another application, that is the file to bring with them.
Audio Spectrum and Audio Waveform
Two effects turn the sound into picture. Both are in the Generate folder of the effect catalog.
- Audio Spectrum draws frequency bars from a real FFT, between a start and end frequency you choose.
- Audio Waveform draws the amplitude envelope.
Both can now follow a path — including a circle, so the spectrum-ring-around-a-logo look is possible — and both have side options, softness, hue interpolation and an adjustable analysis window. (Audio Waveform, in particular, did not draw anything before 0.8.2; it does now.) Neither is the same thing as the layer’s own waveform display in the timeline.
Audio effects
Thirteen audio effects, applied to an audio layer or to a video layer’s own track: the ten After Effects has always had, plus three added to match After Effects 26.3.
| Effect | What it does |
|---|---|
| Bass & Treble | Shelving tone control |
| Parametric EQ | Frequency, Q and gain across three bands |
| High-Low Pass | Cut above or below a cutoff, in either direction |
| Delay | Time, feedback, dry/wet |
| Reverb | Decay, pre-delay, dry/wet, plus Diffusion and Brightness |
| Flange & Chorus | Modulated short delay, with real multiple voices |
| Tone | Generates a tone — five notes and white noise — rather than processing one |
| Modulator | Amplitude and frequency modulation |
| Stereo Mixer | Level and pan per channel |
| Backwards | Plays the source in reverse |
| Compressor | Evens out loud and quiet passages |
| Distortion | Six characters, plus a bitcrusher |
| De-esser | Tames harsh “s” sounds |
Numeric parameters are keyframable on the same schedule as levels, so a filter sweep or a reverb that opens up is ordinary animation. Each effect keeps a stable identity, so keyframes scope to the effect and survive a reorder.
The discrete choices are deliberately not keyframable — High-Low Pass’s direction, and the oscillator shape on Tone, Flange & Chorus and Modulator. Interpolating one would mean a frame that is half a highpass.
Reverb is deterministic. Its impulse response is generated from a seeded hash rather than from random numbers, because a tail that differed per render would make every export of one project sound different — the same rule the frame pipeline follows.
Backwards reverses the source, not the graph. It is applied before the audio graph exists, and a trimmed clip has its offset mirrored along with it — without that, a clip trimmed to 2–4 s of a ten-second file would play 6–8 s backwards, in time, with no error to tell you.