ferraus gain

Apply a fixed gain, overall or per channel

Synopsis

ferraus gain <input> [options] [-o <output>]

What it does

Makes the audio louder or quieter by a fixed amount, in decibels (-6dB) or as a factor (0.5x). Give per-channel values as L=-3dB,R=0dB (or 1=..,2=.. for any channel number; unlisted channels are unchanged), like Audition's Amplify. Warns when the result clips.

This command is also an fx stage and a pipeline op: ferraus fx in.wav -o out.wav --fx "gain:key=value".

Examples

Turn the vocal down 6 dB

ferraus gain vocal.wav --by -6dB -o vocal_quiet.wav

Pull the left channel down 1.5 dB

ferraus gain mix.wav --by L=-1.5dB,R=0dB -o mix_balanced.wav

Double the amplitude inside an effects chain

ferraus fx in.wav -o out.wav --fx gain:by=2x --fx fade:out=3s

Options

Global options

Every command also accepts the global options (-o, --json, --dry-run, --overwrite, --progress, ...). See Global options.

Exit codes

Common mistakes

• Forgetting that outputs are never overwritten: pass --overwrite or a new -o path when re-running.

For models

• MCP tool: ferraus_gain
• Schema: ferraus schema gain
• Pipeline: { op: gain, args: { ... } } (flag names with _ instead of -)
• fx stage: yes

{"command": "gain", "defaults": {"by": "0dB", "mix": "100%"}}