CLEANGRABOpen the tool →

Remove hissing noise behind a voice recording

By ShinobiTools Team · Last updated: August 2026

If your recording has a hissing, sissing background — mic self-noise, static, room hiss — CleanGrab pulls that out for free. If the hiss is sharp S and T sounds in the voice itself, read on before you upload.

Two problems share the word "sibilance"

"Sibilance" gets used for two different problems, and CleanGrab only fixes one of them. We measured this directly rather than guessing: we fed a clean speech recording through CleanGrab and compared the sibilant band (4-9 kHz, where S and T sounds live) against the total signal, before and after. It came back at -7.3 dB both times — completely unchanged. CleanGrab removes hissing background noise (mic self-noise, static, a noisy room), but it does not touch sharp S/T peaks that are already baked into the voice itself. If your recording sounds harsh every time you say an S, that is vocal sibilance, and no background-noise tool fixes it — including this one. We'd rather say that plainly than sell it as a de-esser.

What CleanGrab removes here

The background half of the problem — a hissing, sizzling noise floor sitting under the whole recording — is ordinary background hiss, and our model removes it the same way it removes hum: mic self-noise, static from a badly-gained room, fan and air hiss layered underneath the voice.

How to remove the background hiss
  1. Open CleanGrab and drop your recording in.
  2. Start with Balanced strength.
  3. If 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.
If it's the S sounds themselves, not the background

That's vocal sibilance, and it comes from mic placement and EQ, not background noise, so a background-noise tool — any of them, not just this one — can't remove it without damaging the voice. Two things that actually work:

Do that first, then bring the file here if there's still hiss or hum sitting behind it — the two problems stack, and fixing one doesn't fix the other.

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.

Steady buzz instead of hiss? See removing hum and hiss. Clothing or cable noise? See removing fabric rustling noise.

Common questions

Does CleanGrab work like a de-esser?

No — a de-esser targets sharp S/T peaks in the voice itself, and CleanGrab doesn't touch those (we measured no change in the 4-9 kHz band on a clean test recording). CleanGrab removes background hiss and static instead. For true vocal sibilance, use a dedicated de-esser or move the mic.

Why does my recording still sound harsh on S sounds after cleaning it?

Because that harshness is in the voice itself, not the background, so removing background noise doesn't change it. Pull the mic back slightly and off-axis, or run a de-esser plugin — see above.

What's the difference between hiss and sibilance?

Hiss is a steady background noise floor (mic self-noise, static, room noise) that sits under the whole recording regardless of what's being said. Sibilance is loud only on S and T sounds, because it's part of the voice. CleanGrab removes the first, not the second.

Will it still help if my recording has both problems?

Yes — cleaning the background hiss first often makes the recording sound much better even if the S sounds are still sharp, since the two noises were stacking on top of each other.

What happens to my file?

No. Your upload is deleted the moment it's processed and the cleaned file is wiped from the server within 45 minutes. Nothing is stored, shared or used to train anything — see privacy.