Audio Repair and Restoration
How to remove a cough or one-off noise in REAPER
Published August 27, 2026
The first thing to check is where the noise sits. If the cough, squeak, or thump lands in a gap between words or phrases, the clean fix is to zoom in, split the item on both sides of the noise with S, and either mute that little piece or replace it with a copy of nearby room tone so the hole does not stand out. REAPER’s automatic crossfades smooth the seams. If the noise lands on top of the voice, stock tools can only reduce it, not erase it cleanly: a short volume dip, a narrow ReaEQ cut for a ringing squeak, or REAPER’s basic spectral edit. A noise-reduction plugin like ReaFIR is built for steady background noise and will not remove a one-off. Sometimes the honest fix is to re-record that one line.
A single unwanted sound is one of the most frustrating things in a recording, because the take is otherwise fine. A cough, a chair squeak, a desk thump, a page turn, a stomach rumble, a dog in the next room: one noise, and the whole line feels unusable. The good news is that most one-off noises can be dealt with in REAPER using only the tools that ship with it. The bad news is that a few cannot, and knowing the difference up front saves you a lot of wasted effort.
This guide is about a single, non-repeating noise: an event that lasts a fraction of a second to a second or two and does not come back. If instead you have repeating digital clicks and pops or a continuous crackly texture across the whole file, that is a different problem with a different fix, covered in how to fix crackle and clicks in a recording in REAPER. If the whole recording has a steady hiss or hum underneath it, see how to reduce background noise in a podcast in REAPER instead. This one is about the single sound that should not be there.
Step one: find out where the noise sits
Everything downstream depends on this, so do it first. Zoom in on the noise and listen a few times. You are answering one question: does the noise happen in a pause, or does it happen while the voice, instrument, or music is playing?
Zoom right in
Scroll to the spot and zoom in horizontally until the noise is a clear, separate shape on the waveform. Most one-off noises like a cough or a thump show up as an obvious burst you can see, not just hear.
Is there voice under it?
Play just before and just after. If there is a silent or near-silent gap around the noise, you are in the easy case. If the noise sits on top of words or a sustained note, you are in the hard case.
Note the type
A short spike (a thump or a single knock) is easier than a broadband burst (a cough or a laugh), which is easier than a ringing tone (a chair or hinge squeak at a fixed pitch). The type points you at the right tool below.
The easy case: a noise in a gap
When the noise sits in a pause, you can simply remove that slice of audio. In REAPER, put the edit cursor just before the noise and press S to split the item, then move to just after the noise and press S again. You now have a small item containing only the noise. Select it and either mute it or delete it.
Do not delete the time, only the sound. If you close the gap and shift everything after it, you can pull the track out of sync with other tracks or with a video. Mute or clear the little item in place, or patch it as below. Leave the timeline where it is.
The catch is that pure digital silence often stands out more than the noise did, because the natural room hiss suddenly drops to nothing and then returns. The fix is to patch the hole with room tone.
Grab some room tone
Find a quiet passage elsewhere in the same recording, a moment with no talking but the natural background of the room. Make a time selection over a clean stretch of it.
Copy it over the hole
Copy that room-tone selection and paste it onto the gap where the noise used to be, on the same track. It only needs to cover the hole. A copy that is slightly longer than the gap gives you room to blend the edges.
Let the crossfades blend it
Overlap the patch slightly with the audio on each side. REAPER creates a short crossfade at overlaps automatically, which hides the seam. You can set the default crossfade length under Preferences, Project, Media Item Defaults if the default feels too short or too long.
Your ear is not really listening for the words in a pause. It is listening for continuity. A patch of the same room’s quiet background keeps that continuity, so the edit becomes invisible. This is the same cut-and-crossfade skill used to tidy spoken word, so if you clean up talk tracks often it is worth learning the wider workflow in how to edit out filler words and breaths in REAPER.
The hard case: a noise on top of the voice
When the noise overlaps speech or a held note, you cannot cut it out, because cutting it would take the good sound with it. Here you are reducing the noise, not removing it, and honesty matters: the result is usually better, not perfect. Try these in order, easiest first.
1. Dip the volume for a brief spike
If the noise is short and mostly louder than the voice under it, a quick volume dip can knock it back without anyone noticing. Show the track’s volume envelope, add points just before and just after the noise, and pull the level down in that tiny window. REAPER has no destructive pencil tool for redrawing the waveform itself, so a volume envelope is the stock way to do this kind of surgical level move. It works best on a fraction-of-a-second thump or knock, less well on a long cough.
2. Notch a ringing squeak with ReaEQ
Some one-off noises are tonal: a chair or hinge squeak, a phone vibrating on a desk, a ringing chime. Those live at a specific pitch. Add ReaEQ, take one band, set it to a narrow peaking cut, and sweep to find the frequency of the ring. A deep, narrow cut there for the length of the noise can reduce it while leaving the voice mostly intact. Automate the band in and out so you are not cutting that frequency for the whole track. This does nothing for a broadband cough, which has no single pitch to remove.
3. Try REAPER’s spectral edit for a small area
REAPER does include a basic spectral editing feature. With an item selected, the action Spectrogram: Add spectral edit to item lets you draw a box over a region of time and frequency and attenuate what is inside it. For a small, well-defined noise this can help. Be realistic about it: REAPER’s spectral tools are limited and fiddly compared with dedicated repair software, and they will not intelligently rebuild audio the way a purpose-built spectral-repair tool does. Treat it as a reducer, not an eraser.
A subtractive noise-reduction plugin such as ReaFIR in Subtract mode learns a profile of steady, constant background noise and removes it across the whole file. A cough or squeak is a one-time event, so there is no steady profile to learn, and pushing ReaFIR hard enough to catch it will smear the voice. Use ReaFIR for a constant hum or hiss, not a single noise. A fixed tonal hum has its own method in how to remove hum from a recording in REAPER.
| Noise | Where it sits | Best stock move |
|---|---|---|
| Cough, laugh, page turn | In a gap | Split with S, mute or clear, patch with room tone |
| Desk thump, single knock | Over the voice | Short volume-envelope dip |
| Chair or hinge squeak, ring | Over the voice | Narrow ReaEQ notch, automated in and out |
| Cough, broadband burst | Over the voice | Spectral edit to reduce, or re-record the line |
| Steady hiss or hum | Whole file | Not a one-off, use noise reduction instead |
What stock tools will not do
REAPER is generous with what it includes, but spot repair has real limits, and it is fairer to know them before you spend an hour on a take that cannot be saved.
- It will not cleanly lift a loud cough off a sustained note. When the noise fully overlaps the good sound and is as loud or louder, no stock move separates them without an obvious scar.
- REAPER has no dedicated de-click or spectral-repair engine like the specialist restoration tools. Its spectral edit reduces a region; it does not intelligently reconstruct what was underneath.
- Patching only works if you actually have clean room tone to borrow. If every second has talking or music, there is nothing to paste in.
- It cannot invent audio that was masked. If the voice under the cough is gone, it is gone.
A one-off noise in a pause almost always disappears completely. A one-off noise over the voice usually gets quieter and less distracting, which is often enough. When it does not, re-recording that single line, punched in against the existing take, is usually faster and cleaner than fighting a repair that will never fully work.
If it still sounds wrong
Quick troubleshooting order when the edit is not sitting right:
- You hear a click at the edit. Your splice has no crossfade. Overlap the items slightly, or lengthen the default crossfade, so REAPER blends the join.
- The patch sounds dead. The room tone you pasted is too quiet or from a different-sounding spot. Grab tone from nearer the edit, and match its level to the surrounding background.
- The timing drifted. You deleted time instead of clearing in place. Undo, and this time mute or patch without closing the gap.
- The notch thins the voice. Your ReaEQ cut is too wide or left on too long. Narrow it and automate it to open only for the length of the noise.
- Nothing is working. The noise is broadband and fully over the voice. This is the re-record case, not a repair case.
Deal with a one-off noise by first asking where it sits. In a gap, split it out with S and patch the hole with room tone so the silence does not show. Over the voice, reduce it with a short volume dip, a narrow ReaEQ notch for a tonal squeak, or REAPER’s basic spectral edit, and accept that the result is quieter rather than gone. Skip the noise-reduction plugin, which is built for steady noise, and re-record the line when the noise simply cannot be separated.
Sources
- Cockos, REAPER User Guide (current version 7.79, released August 2026) - splitting items, crossfades and the default crossfade length, and track volume envelopes. reaper.fm/userguide
- Cockos, “ReaPlugs” - ReaFIR described as an FFT-based dynamics/EQ tool whose Subtract mode removes a learned profile of steady noise, bundled with REAPER. reaper.fm/reaplugs
- Sound On Sound, “Spectral Editing In REAPER” - REAPER’s native spectral editing exists but is limited in scope compared with dedicated spectral-repair software. soundonsound.com/techniques/spectral-editing-reaper
- Cockos Forums, “how to remove this Cough Sound to get a best result?” - community discussion confirming that one-off sounds are handled by editing and reduction, not by steady-noise removal. forum.cockos.com