How to Use Impulse Response Reverb in Audacity

Audacity can process audio using convolution reverb and impulse response (IR) WAV files, but it requires a third-party plugin because the software does not feature a native convolution engine out of the box. While Audacity includes a built-in algorithmic reverb, loading true impulse response files requires installing a compatible VST or VST3 plugin that supports IR loading. This article explains how to set up and apply convolution reverb using IR WAV files inside Audacity.

Does Audacity Support Native Convolution?

Audacity's built-in "Reverb" effect generates artificial reverberation mathematically using delay networks and filters (algorithmic reverb). It cannot directly import or read .wav impulse response files.

While Audacity includes a specialized Nyquist command capable of mathematical convolution between two audio tracks, it is cumbersome, destructive, and lacks the controls—such as pre-delay, wet/dry mix, and filtering—essential for professional audio editing. Therefore, using a dedicated third-party VST plugin is the standard and most efficient method.

Step 1: Install an IR-Compatible Reverb Plugin

To use IR files, you must download a free or paid third-party plugin capable of loading custom WAV impulses. Notable free options that run inside Audacity include:

• Impulse Record Convology XT: A free plugin designed specifically for convolution, offering an easy browser to load external WAV files.
• MeldaProduction MConvolutionEZ: A lightweight convolution processor that allows custom impulse loading.
• SIR Audio Tools SIR1: A classic, free 32-bit/64-bit VST convolution processor (depending on your Audacity version).

Install your chosen plugin to your system’s standard VST or VST3 directory.

Step 2: Enable the Plugin in Audacity

Once installed, register the plugin inside the Audacity interface:

1. Open Audacity.
2. Navigate to Effect > Plugin Manager (or Add / Remove Plug-ins in older versions).
3. Locate your installed convolution plugin in the list.
4. Select the plugin, click Enable, and then click OK.

The plugin will now appear in your Effect drop-down menu.

Step 3: Apply the Impulse Response to Your Track

1. Select the audio track or section you want to process.
2. Open your installed convolution plugin from the Effect menu.
3. Use the plugin interface's "Load," "Import," or folder icon to browse to your .wav impulse response file.
4. Adjust the Dry/Wet balance to control the intensity of the space.
5. Preview the audio to ensure the decay and tone match your requirements.
6. Click Apply to render the convolution reverb directly onto the waveform.

Tips for Using IR Files in Audacity

• Match Sample Rates: Ensure your project sample rate (e.g., 44.1 kHz or 48 kHz) matches the sample rate of the IR WAV file to prevent pitch or timing artifacts.
• Prevent Clipping: Convolution adds significant energy to audio. Lower the input gain or leave sufficient headroom before processing to avoid digital distortion.
• Add Room for Tails: If you are applying reverb to the end of a track, add a few seconds of silence to the end of the audio selection prior to processing so the reverb tail does not cut off abruptly.