A muffled sound quality is often achieved when you’re speaking from another room, under a blanket, pillow or behind some kind of object that absorbs your vocal frequencies.
This phenomenon happens because higher-end audio frequencies get blocked and absorbed. However, lower-end frequencies manage to get through, leaving you with low-end frequencies only.
We can mimic this effect in Premiere Pro using an equalizer to cut out the higher-end frequencies while maintaining the lower end.
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Here’s a step-by-step guide:
- Drag your audio onto the timeline
- Go to Effects
- Find the FFT Filter effect and drag it onto the audio clip
- Go to Effect Controls and click Edit next to Custom Setup
- Check the Spline Curves box for smoother application
- Create two extra points and adjust the curve to cut out frequencies above 1kHz (Example below).
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Adjust the FFT Filter curve to your preference. Cutting out more of the high end will make your audio sound more muffled and incomprehensive.
Original audio:
Muffled audio: