# Add Effects to an Audio File Add reverb, echo, chorus, tremolo and compression to audio in your browser — chain effects in one pass and download MP3, WAV or more. No upload. ## Run it - **CLI:** `gizza tool audio-effects-rack 'url=https://example.com/input' 'reverb=none' 'echo=0' 'chorus=none' 'tremolo=0' 'compression=none' 'format=mp3'` - **Web:** https://gizza.ai/tools/audio-effects-rack/ - **Agents:** machine-readable descriptor (parameters JSON Schema) at https://gizza.ai/tools/audio-effects-rack/tool.json ## Inputs - `file` — Audio _(file; accept: audio/*)_ - `reverb` — Reverb _(field)_ - `echo` — Echo delay (ms) _(field)_ - `chorus` — Chorus _(field)_ - `tremolo` — Tremolo rate (Hz) _(field)_ - `compression` — Compression _(field)_ - `format` — Output format _(field)_ ## Output - Processed audio (audio) ## Query parameters Open the tool pre-filled and auto-run via URL: - `reverb` — Reverb - `echo` — Echo delay (ms) - `chorus` — Chorus - `tremolo` — Tremolo rate (Hz) - `compression` — Compression - `format` — Output format - `url` — fetch the input file from a public URL (CORS-permitting) Example: `https://gizza.ai/tools/audio-effects-rack/?url=https://example.com/input&reverb=none&echo=0&chorus=none&tremolo=0&compression=none&format=mp3` --- ## An effects rack in your browser Pick an audio file and chain up to five classic effects in a single ffmpeg pass — no upload, no account, everything runs locally in the browser tab. The stages are applied in the usual musical signal order: 1. **Compression** — evens out loud/quiet swings (`none`, `light`, `medium`, `heavy`). This is loudness dynamics, not file-size compression. 2. **Chorus** — detuned doubling for width and shimmer (`none`, `light`, `deep`). 3. **Tremolo** — a rhythmic amplitude wobble at 0.1–20 Hz (`0` = off). 4. **Echo** — a single discrete repeat, 0–1000 ms delay (`0` = off). 250 ms is a quarter-second slapback. 5. **Reverb** — a sense of space (`none`, `room`, `hall`, `plate`). Any stage left at `none` or `0` is skipped, so you only pay for what you use. At least one stage has to be active — an all-off request is rejected instead of wasting a re-encode on an unchanged file. ### Worked example You have a dry vocal take, `vocal.wav`, that sounds flat and lifeless. Choose **Compression → Medium** to bring it forward, **Chorus → Light** for a touch of width, **Echo → 250 ms** for a slapback, and **Reverb → Hall** for space; leave **Tremolo** at `0`. Keep the format on **mp3** and you get back `vocal-fx.mp3` with the whole chain baked in. Too washed-out? Drop reverb to `room` and echo to `0`. Want a lo-fi pulse instead? Set **Tremolo → 6 Hz** and **Reverb → Room**. ### What each stage does - **Compression** — `light` for a gentle level-up, `heavy` to squash hard for a loud, upfront, "radio" sound. Heavier presets use a lower threshold, higher ratio and more make-up gain. - **Chorus** — `light` is one gentle voice; `deep` is two detuned voices for a lush, wide shimmer. Great on thin synths, pads and backing vocals. - **Tremolo** — a fixed 70% depth wobble; slow rates (2–4 Hz) pulse, faster rates (8–12 Hz) shimmer. Above ~20 Hz it stops sounding like tremolo. - **Echo** — one clean repeat with a fixed decay. Short delays (80–150 ms) thicken; longer ones (300–500 ms) read as a distinct doubling. - **Reverb** — `room` is tight and small, `hall` is big with a long tail, `plate` is bright and dense. It's a lightweight multi-tap approximation, so it runs the same everywhere without an impulse-response file. ### Limits and edge cases - Input files up to 10 MiB; any format ffmpeg can decode works. - Echo delay is capped at 1000 ms and tremolo at 20 Hz — beyond those the effects stop being musical and start adding artefacts. - Tremolo can't run between 0 and 0.1 Hz (ffmpeg's `tremolo` rejects it); use `0` for off or `0.1` and up. - Effects are additive and can push loud audio into clipping. If the result crackles, ease off compression make-up or lower the level first with audio-volume-adjust, then add effects. - Output is re-encoded (mp3/ogg at 192 kbps; wav/flac lossless; m4a AAC), and any embedded album-art image stream is dropped. ## FAQ
In what order are the effects applied? Always compression → chorus → tremolo → echo → reverb, the standard musical signal chain: dynamics first, then modulation, then time and space. Compressing before reverb keeps the tail smooth; reverberating last means the space wraps the whole processed sound. The order is fixed so the result is predictable — you switch stages on and off, not reorder them.
Can I use just one effect? Yes. Leave every other stage at `none` or `0` and only the one you set is added to the chain — e.g. reverb `hall` alone, or echo `250` alone. The only rule is that at least one stage must be active; an all-off request is rejected so you don't re-encode a file for no change.
Is this "compression" the same as making the file smaller? No. Here **compression** means dynamic-range compression — it narrows the gap between the loudest and quietest parts so the audio sounds more even and upfront. It does not shrink the file; for smaller files pick a lossy format (mp3/ogg/m4a) or use the separate audio-compress tool.
What's the difference between echo and reverb here? Echo is one discrete repeat you can hear as a separate copy (set by the delay in milliseconds). Reverb is many overlapping reflections blurred into a continuous sense of space (room/hall/plate). Use echo for a slapback or doubling effect, reverb to place the sound in a room.
Is my audio uploaded anywhere? No. The page downloads an ffmpeg WebAssembly build once and then processes your file locally in the browser tab — the audio never leaves your device.
## Related tools - [Compress an Audio File](https://gizza.ai/tools/audio-compress/): Shrink MP3, WAV, M4A or any audio file right in your browser — pick a target bitrate (96 kbps default) and format. Nothing is uploaded, free. - [Convert an Audio File](https://gizza.ai/tools/audio-convert/): Convert any audio file to MP3, WAV, OGG, FLAC or M4A right in your browser — pick a bitrate for lossy formats. Runs locally, nothing is uploaded, free. - [Equalize an Audio File](https://gizza.ai/tools/audio-eq/): Equalize any audio file right in your browser — boost or cut bass, mid and treble in dB, then save as MP3, WAV and more. Nothing is uploaded, free. - [Fade an Audio File In and Out](https://gizza.ai/tools/audio-fade/): Add a smooth fade-in and fade-out to any audio file right in your browser — pick the lengths in seconds. Nothing is uploaded, free. - [High-Pass Filter Audio](https://gizza.ai/tools/audio-highpass-filter/): Apply a high-pass (low-cut) filter to audio in your browser — set a cutoff frequency to strip rumble, hum, and handling noise.