What is spectral gating and when would you apply it in post-production?

• A. A Mastering Process That Boosts Overall Loudness.
• B. A Dynamic Range Compressor Applied to Music.
• C. A Noise Reduction Technique That Uses a Gate in the Spectral Domain to Reduce Broadband Hiss While Preserving Speech.
• D. A Reverb Effect Used for Space Simulation.

Answer: (C)

Spectral gating is a noise reduction technique that works in the frequency domain. It builds a noise profile from a quiet portion of the recording and then attenuates or gates frequency bands where noise energy exceeds a threshold, while leaving the actual speech or desired signal intact. This lets you reduce broadband hiss and ambient noise without squashing the voice.

In post-production, you’d apply this on dialogue tracks to clean up noisy environments—think hiss, air conditioning, or distant hum—especially in quiet or dialogue-only scenes where the noise is distracting but the speech needs to stay clear. It’s a targeted cleanup tool for speech, not a mastering processor or a reverb/compression effect, and overdoing it can introduce artifacts, so use modestly to preserve natural voice quality.