Remove Hiss from Audio
That constant high-frequency "sssss" from cheap mics, gain boosts and old cassette tapes is broadband hiss. This tool estimates the hiss floor and subtracts it, leaving a quieter, cleaner recording.
How it works
We take a short-time spectrum of the audio, estimate the noise floor from the quietest frames, and subtract it from every frame (spectral subtraction). The result is an audible drop in the constant hiss.
What it's good for
- Cassette and tape transfers
- Cheap or hot-gain microphones
- Old digitized recordings
- Hissy voice memos
Details
- Engine
- DSP
- Formats
- MP3, WAV, M4A, FLAC, OGG, AAC
- Price
- Free to try
Frequently asked questions
Hiss is high-frequency broadband noise ("ssss"); hum is a low-pitched tone at 50/60 Hz from electrical interference. Use the de-hum tool for that low buzzing instead.
Aggressive hiss removal can soften the very top end. We apply moderate subtraction by default to keep brightness; you can re-run for heavier cleanup if needed.
No — hiss removal is a fast signal-processing filter that runs almost instantly, even on long files.
It estimates the noise floor from the quietest frames across the whole file, so a dedicated silent gap helps accuracy but is not strictly required.
Yes. Spectral subtraction works on music, but pushing it hard can introduce a faint watery artifact, so use moderate amounts on tonal or sustained material.
No. This tool takes audio formats such as MP3, WAV and FLAC; extract the audio from a video first if needed.
Yes. Each channel is processed independently, so the hiss drops across the full stereo image, not just one side.