# Spectral Denoiser

Reduce broadband noise with a spectral filter chain

> Canonical page: https://elysiatools.com/en/tools/spectral-denoiser

- **Category:** Media

- **Keywords:** audio, noise reduction, denoise, spectral, ffmpeg, afftdn

## Overview

Uses a practical FFmpeg chain with high/low cuts, afftdn, optional hum removal, and limiter protection to reduce broadband noise without a noisy guesswork model.

## Inputs

- **Audio File** (file): Select an audio file
- **Noise Reduction** (number)
- **Low Cut (Hz)** (number)
- **High Cut (Hz)** (number)
- **Remove Hum** (checkbox)
- **Preserve Voice** (checkbox)
- **Output Format** (select)

## When to use

- When you need to clean up background hiss, static, or hum from voice recordings, podcasts, or interviews.
- When you want to apply precise high-pass and low-pass filters to eliminate low-frequency rumble or high-frequency noise.
- When you need a reliable, non-destructive spectral noise reduction tool that preserves vocal clarity and prevents clipping.

## How it works

- Upload your audio file and set the desired noise reduction level in decibels.
- Configure the low-cut and high-cut frequency thresholds to filter out unwanted low-end rumble and high-end hiss.
- Enable optional settings like hum removal to target electrical interference, and choose your preferred output format such as WAV, FLAC, or MP3.

## Use cases

- Cleaning up podcast episodes recorded in non-acoustic environments with noticeable background hiss.
- Removing low-frequency air conditioning rumble and electrical hum from voiceover tracks.
- Restoring archival audio recordings by filtering out tape hiss and high-frequency static.

## Frequently asked questions

### What audio formats are supported for output?

You can export your processed audio as WAV, FLAC, MP3, M4A, or OGG.

### How does the 'Preserve Voice' option work?

It optimizes the spectral filter chain to protect human speech frequencies, preventing vocal distortion during noise reduction.

### What is the maximum file size I can upload?

The tool supports audio files up to 100 MB in size.

### What does the 'Remove Hum' option do?

It targets and filters out constant low-frequency electrical hums, typically caused by power grids or ground loops.

### How does the spectral denoiser reduce noise without AI?

It uses FFmpeg's afftdn filter, which analyzes the audio spectrum to isolate and attenuate steady broadband noise.

## Related tools

- [FFmpeg Audio Noise Reduction](https://elysiatools.com/en/tools/ffmpeg-audio-noise-reduction): Professional audio noise reduction using FFmpeg advanced filters (highpass, afftdn, loudnorm) for optimal audio cleaning
- [Audio Band-Reject Filter](https://elysiatools.com/en/tools/audio-band-reject-filter): Remove a specific band of frequencies
- [Audio Notch Filter](https://elysiatools.com/en/tools/audio-notch-filter): Remove a very narrow frequency band (e.g., hum)
- [Classroom Recording Cleaner](https://elysiatools.com/en/tools/audio-classroom-recording-cleaner): Clean lecture recordings with speech-focused EQ, hum reduction, peak control, and optional long-silence trimming.
- [Audio Mouth Click Finder](https://elysiatools.com/en/tools/audio-mouth-click-finder): Detect-style repair for lip smacks, saliva clicks, mouth ticks, and small voice-over clicks.
- [Audio Noise Gate](https://elysiatools.com/en/tools/audio-noise-gate): Apply a noise gate to remove low-volume noise
- [Audio Noise Reducer](https://elysiatools.com/en/tools/audio-noise-reducer): Remove background noise from audio files using various noise reduction algorithms
- [Audio Decrackler](https://elysiatools.com/en/tools/audio-decrackle): Remove crackles and subtle impulsive noise from audio files. Ideal for restoring old recordings, cassette tapes, and digitized vinyl with surface noise

## Samples

- [Bevy Game Engine Samples](https://elysiatools.com/en/samples/bevy-samples): Bevy Rust game engine examples with ECS, 2D/3D graphics, audio, and game mechanics implementations
- [Godot Engine Samples](https://elysiatools.com/en/samples/godot): Godot Engine examples including 2D/3D games, GDScript, C#, and engine features
- [Copyright-Free FLAC Audio Samples](https://elysiatools.com/en/samples/flac-samples): Lossless FLAC audio samples for testing and development, mirrored from MP3 set with nature sounds and meditation music
- [Copyright-Free MP3 Audio Samples](https://elysiatools.com/en/samples/mp3-samples): Collection of royalty-free audio samples for testing and development purposes including nature sounds, meditation music, and ambient audio