Clean Up Background Noise and Microphone Hiss Online
Unwanted background noise can quickly ruin an otherwise great voice recording. Whether you're recording a podcast, voiceover, meeting, or interview, background rumble, electrical hum, and microphone hiss distract listeners and reduce intelligibility.
AudioKit's Noise Reducer runs entirely in your browser using real-time Web Audio digital signal processing. Your audio is processed directly on your computer or phone—no files are uploaded to external servers, protecting your privacy.
How the Noise Reduction Tools Work
- Noise Gate Threshold: The noise gate silences audio whenever the signal drops below a chosen decibel level. It cuts out ambient room tone, computer fan hum, and air conditioning noise during pauses between words.
- Electrical Hum Removal: Low-frequency electrical hum from power outlets and unshielded cables typically occurs at 50 Hz (Europe/Asia) or 60 Hz (North America). The hum toggle applies steep notch filters at these frequencies to eliminate buzz without affecting the vocal range.
- Hiss Reduction: High-frequency hiss and line noise from budget microphone preamps sit in the 6 kHz to 16 kHz range. The hiss slider rolls off harsh high-frequency noise while preserving vocal clarity and brightness.
Best Practices for Clean Audio
- Don't over-gate: If the gate threshold is set too high (for example, above -30 dB), the beginning and end of soft words may get cut off. Start around -50 dB and adjust gradually until speech sounds natural.
- Keep subtle room tone: Total digital silence between words can sound unnatural. Aim to reduce background distraction rather than trying to achieve an anechoic chamber.
- Irregular sounds vs. steady noise: Spectral and gate filters work best on continuous, steady sounds like fans, hums, and hiss. Sudden sounds like loud clapping, sirens, or dog barks overlap with speech and are best addressed during recording or with multi-track editing.