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Remove hum and hiss from any recording

By ShinobiTools Team · Last updated: July 2026

Upload a recording and get the hum and hiss pulled out — electrical buzz, mic self-noise and steady background static removed while the voice stays natural. Free, no account.

Clean a recording, free →

Two different noises, one upload

Hum is the low, steady buzz from mains electricity or a bad cable ground (50/60 Hz and its overtones). Hiss is the higher, airier background static from a cheap microphone, a room's own noise floor, or a badly-gained recording. Both sit constantly under the voice, and DeepFilterNet3 is built to recognise and remove exactly that kind of steady background noise, not just the voice's own transients.

• Electrical hum and buzz from cables or mains
• Microphone self-noise and hiss
• Steady background static from a noisy room
• Fan and air-conditioning drone that layers under hiss

How to remove hum and hiss

1. Open CleanGrab and drop your recording in.
2. Start with Balanced strength.
3. If hum or hiss is still audible, switch to Strong; if the voice starts sounding thin or processed, drop to Gentle.
4. Download the cleaned MP3 or lossless WAV.

When hum and hiss are the whole problem — and when they're not

On a recording where hum and hiss are the main issue, CleanGrab typically gets you most of the way there in one pass. Heavy room echo and reverb are a harder, separate problem: CleanGrab reduces light echo, but it will not fully erase a very reverberant room. We'd rather say that plainly than promise something the tool can't do.

CleanGrab is tuned for voice and speech — podcasts, interviews, calls, voice memos, lectures. On music or other non-speech audio the result can be poor, and the tool will tell you when it couldn't detect clear speech instead of handing you a mangled file.

Where hum and hiss come from in your own setup

These two noises have completely different causes, and once you know which one you have, you can often remove it at the source in under a minute — which always beats processing it afterwards.

Hum is your mains supply leaking into the audio path. It sits at 50 Hz in Europe and 60 Hz in North America, plus harmonics at 100/150 Hz or 120/180 Hz, which is why it sounds like a low buzz rather than a pure tone. The usual sources:

• A ground loop — the classic. Your laptop charger and your audio interface are both earthed, and the difference between them becomes a hum. This is the number one cause of hum in home recordings.
• A bus-powered interface sharing power with a screen or hub.
• An unbalanced cable running alongside a power lead, or a long unbalanced cable in general — it works as an aerial.
• Dimmer switches, fluorescent tubes and cheap LED drivers in the room, which inject a buzzier, harsher version.

Hiss is the opposite problem: it's the electronic self-noise of your microphone and preamp, and it becomes audible when you have to turn the recording up. So hiss is almost always a symptom of recording too quietly — either the gain was set too low, or the microphone was too far from your mouth and you compensated afterwards.

Thirty seconds at the source beats any processing

Before you upload anything, try these in order. Each one takes seconds and each removes noise completely rather than reducing it:

1. Unplug the laptop charger and record on battery. If the hum disappears, it was a ground loop, and you've just solved it perfectly.
2. Move the microphone and its cable away from power supplies, the back of your monitor, and any plug strip. A hand's width often does it.
3. Get the microphone closer to your mouth. Halving the distance gives you roughly 6 dB more voice at exactly the same noise level — the single most effective thing you can do about hiss.
4. Raise the gain at the microphone or interface, not in the editor. Turning it up afterwards amplifies the hiss by exactly as much as the voice. Aim for peaks around -12 to -6 dB.
5. Switch things off one at a time — light, fridge, air conditioning, fan — while recording a few seconds each. You'll usually find the culprit in one pass.

Then upload whatever is left. Both hum and hiss are the model's best case: steady, predictable, nothing like a voice, so they come out cleanly at Balanced without touching the character of your voice. Hum in particular often vanishes at Gentle, which is worth trying first if the recording is otherwise good.

Common questions