Audacity Mastering Macro: Normalize, Compress, Limit

Mastering audio in Audacity can be streamlined significantly by automating your workflow with custom macros. This guide walks you through creating a reusable mastering chain macro that applies loudness normalization, dynamic range compression, and peak limiting in a single click, ensuring your podcasts, voiceovers, or music tracks achieve a polished, commercial sound with consistent volume.

Step 1: Create a New Macro

  1. Launch Audacity.
  2. Navigate to Tools > Macros... in the top menu bar.
  3. In the left-hand column of the Macro Manager window, click the New button.
  4. Enter a descriptive name for your chain, such as Mastering Chain, and click OK.

Step 2: Add Loudness Normalization

Normalizing first ensures your audio hits the compressor at a predictable level, allowing dynamic processing to behave consistently regardless of the raw recording volume.

  1. Select your new macro in the left panel.
  2. Click the Insert button on the right side.
  3. In the command list, locate and select Loudness Normalization, then click Edit Parameters.
  4. Configure the settings:
    • Normalize to: Perceived Loudness (LUFS)
    • Target value: -16 LUFS (standard for stereo podcasts and web audio) or -19 LUFS (standard for mono voice).
  5. Click OK, then click OK again to add the command to your macro list.

Step 3: Add the Compressor

Compression reduces the dynamic difference between the loudest and quietest sections, resulting in a tighter, more cohesive sound.

  1. Click Insert in the Macro Manager.
  2. Select Compressor and click Edit Parameters.
  3. Adjust the parameters to standard mastering levels:
    • Threshold: -14 dB to -18 dB
    • Noise Floor: -40 dB
    • Ratio: 2:1 or 3:1 (gentle compression suitable for mastering)
    • Attack Time: 0.20 secs
    • Release Time: 1.0 secs
    • Uncheck Make-up gain for 0 dB after compressing (the limiter will manage final levels).
  4. Click OK, then click OK to insert the step.

Step 4: Add the Limiter

A limiter catches any sudden transients and establishes an absolute ceiling, preventing digital clipping and distortion.

  1. Click Insert in the Macro Manager.
  2. Select Limiter from the command list and click Edit Parameters.
  3. Configure the limiter:
    • Type: Soft Limit
    • Input Gain (Mono/Left & Right): 0 dB
    • Limit to: -1.0 dB (leaves enough headroom to prevent inter-sample clipping during MP3 or AAC export)
    • Hold: 10.0 ms
  4. Click OK, then click OK to add it to the chain.

Step 5: Save and Run the Macro

  1. Verify the order of operations in the command list:
    1. Loudness Normalization
    2. Compressor
    3. Limiter
  2. Click the Save button in the Macro Manager, then click Close.

To apply the macro to your project, open your audio file, select the track (or press Ctrl + A / Cmd + A to select all), navigate to Tools > Apply Macro, and select your custom mastering macro. Audacity will automatically process the entire sequence sequentially.