Alexis Kestler
Hey friend! Do you ever record audio only to play it back and cringe at all the background noise? I feel your pain. Unwanted noise like humming, hissing or rumbling can totally ruin an otherwise good recording.
But don‘t worry – I‘m here to help you fix it! In this detailed guide, I‘ll cover everything you need to know to effectively remove noise from audio recordings and make them sound crystal clear.
Why Getting Rid of Noise Matters
Before we dig into the tools and techniques, let‘s talk about why eliminating background noise is so important for great quality audio.
Here are some of the big ways noise hurts your recordings:
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It‘s distracting – Hissing, humming or crackling grabs the listener‘s attention instead of your intended audio content.
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It sounds unprofessional – Too much noise signals sloppy production quality.
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It causes listening fatigue – Noise makes your ears work harder and get tired more quickly.
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It masks detail – Subtleties and nuance in the audio can get lost behind the din.
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It flattens dynamics – Noise squashes the contrast between loud and soft sounds.
From podcasts to videos to music, noise is the enemy! Now let‘s look at why it sneaks into recordings in the first place.
What Causes Noise in Audio Recordings
Noise in audio usually boils down to a few common culprits:
Electrical Interference
Motors, wiring, lights, computers and other electronics generate electromagnetic interference that can get induced into audio signals. This creates buzzing, humming and static-like noise.
Poor Microphone Technique
How you set up and use microphones makes a big difference. Too much gain and distant miking accentuate noise. Good technique minimizes it.
Environmental Sounds
Any ambient sounds around the mic will get picked up – air conditioning, computer fans, traffic, talking, etc. Controlling the environment is key to a clean recording.
Low-Quality Gear
Cheaper audio equipment tends to be more susceptible to interference and electronic noise. Better mics, preamps and interfaces can help.
So in summary, the noise itself comes from electronics and the environment. And mics will always pick up some of it unless you‘re recording in a totally dead studio.
The good news is, we can significantly reduce noise using some simple best practices and audio editing tools. Let‘s go over some recording tips first.
7 Ways to Reduce Noise When Recording Audio
Preventing noise starts with solid microphone technique and recording habits. Here are my top suggestions for keeping noise down in the first place:
Record in a Quiet Space
Find a peaceful, noise-free room to record whenever feasible. Turn off AC, computer fans, telephones, etc.
Get the Mic Close to the Source
Position the mic as close as practical to maximize the signal you want relative to the noise.
Use a Directional Microphone
Cardioid mics reject off-axis sounds, reducing ambient noise. Shotguns are even more directional.
Add Acoustic Treatment
Sound absorbing panels tame echo and muffle ambient noise in the room.
Use a Noise Gate
Noise gates set a volume threshold to mute sounds below a set level, eliminating low-level noise.
Record a Room Tone Sample
Capture the ambient noise itself as a reference for noise reduction later.
Optimize Gain Staging
Set input gain just high enough to get a strong signal without adding excess noise.
Combining these recording best practices goes a long way in preventing noise. But you‘ll likely still need some tools to clean up tracks in post-production. Let‘s explore those now.
Top 10 Tools to Remove Background Noise from Audio
When undesirable noise does rear its ugly head, these powerful audio editors can fix it:
1. iZotope RX
In my opinion, RX by iZotope is the undisputed industry leader for audio restoration and noise reduction. It‘s used daily by top sound engineers to clean up recordings in music, film, TV and more.
RX packs a ton of professional-grade tools like spectral repair, dereverb and adaptive noise reduction into one robust software.
It works wonders removing consistent broadband noise like hum, hiss, rumble or computer fans. The spectral editor lets you visually select and erase any narrow band resonances. This is perfect for eliminating AC hum or feedback tones.
RX also features click/pop removal, dialog isolation, degritting, powerful dynamics tools and so much more. It‘s the Swiss Army knife for restoring noisy audio. Highly recommended!
2. Acon Digital Acoustica
If you want efficient, dedicated audio restoration tools at a great value, check out Acoustica by Acon Digital.
It features top-notch noise reduction that analyzes your audio and applies frequency-based attenuation to suppress noise. This works extremely well for consistent broadband hum/hiss.
For crackles, clicks and pops, Acoustica‘s DeClicker tool visually detects and suppresses impulse noise based on its profile. Very handy!
You also get parametric EQ, declipping, dynamics processing and batch processing capabilities for serious audio cleanup and restoration work.
3. Audacity
If you‘re looking for a free, open-source option, Audacity is massively popular for good reason. It comes packed with effects and editing tools, including capable noise reduction.
Under Effects > Noise Reduction, you first sample the ambient noise itself. Audacity analyzes this to build a spectral "fingerprint" of the noise.
When you apply reduction to your recording, it suppresses frequencies that match the noise profile. This successfully removes consistent broadband noise like hum or hiss.
Audacity‘s tools work best on constant noise. Variable background noise or sudden sounds like clipping are harder to fix. But overall, Audacity provides free, DIY noise reduction. Well worth a try!
4. Sound Forge Noise Reduction
If you‘re on Windows and want premium noise reduction capabilities, Sound Forge from Magix is an excellent choice.
It features a dedicated Noise Reduction module that analyzes a noise sample to build a spectral profile. Once mapped, it applies subtractive filtering to strip away broadband noise across your entire recording.
You get realtime controls to tweak the reduction settings while previewing the results. Very handy for finding the ideal balance between noise removal and audio quality.
With its spectral editing tools, click repair, EQ matching and more, Sound Forge provides comprehensive audio cleanup for Windows users.
5. ReaFir
If you use the REAPER digital audio workstation, it comes bundled with ReaFir – a powerful noise reduction plugin that also works great as a standalone effect.
ReaFir analyzes a noise sample to build a reduction filter. Once configured, it applies subtractive filtering, damping and gating to strip away consistent broadband noise.
Separate processing modes target overall broadband noise, isolate tonal resonances and tackle standard AC hum. Global filtering lets you shape the noise profile‘s frequency response so you can better preserve the source audio.
For serious audio cleanup work, ReaFir provides extensive parametric controls. But it also offers simple sliders for quick noise reduction balancing. Impressive stuff!
6. Celemony Capstan
The engineers at Celemony are doing some of the most innovative work in audio cleanup and restoration algorithms.
Their flagship software Capstan utilizes advanced artificial intelligence to detect and reduce unwanted noise often better than traditional tools.
In addition to great noise reduction, Capstan also offers handy repair tools:
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Smart Hum Removal – Detects and eliminates AC power hum
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DeBuzz – Eliminates complex stable buzzing noises
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DeCrackle – Repairs crackles without dulling transients
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DeClip – Reconstructs peaks clipped during recording
Capstan analyzes your audio and provides optimized suggestions to clean it up. You can tweak the settings as needed or just run with its intelligent presets for great results with little effort. Impressive!
7. Accusonus ERA Bundle
The ERA Bundle from industry leader Accusonus packs several handy audio repair tools into a suite of plugins:
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ERA De-noise – Reduces constant broadband noise
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ERA De-hum – Eliminates power line hum
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ERA De-reverb – Tames excessive reverb
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ERA De-esser – Controls harsh sibilance
Each one utilizes AI to analyze your audio and make intelligent repair suggestions. This makes it super easy to clean up noise, hum, echo, harshness and more.
The ERA plugins work great standalone but also integrate into major DAWs like Pro Tools, Logic, Ableton and more. Powerful stuff!
8. Waves X-Noise
Waves makes some of the top audio plugins on the market, including the surgical X-Noise reduction tool.
It starts by analyzing a selected noise sample to build a spectral profile. X-Noise uses advanced separation to isolate the noise from the source audio even at very low levels.
Once it learns the noise fingerprint, X-Noise applies frequency-based gain reduction to strip the noise away across your entire recording.
Separate Learn and Reduce modes let you re-sample the noise profile. This allows it to adapt to changes over time. Plus global filtering helps shape the reduction curve.
For reliable broadband noise removal, X-Noise is surgically precise. It works great as a plugin or standalone app.
9. Acon Digital DeNoise
When you just need affordable, easy-to-use noise reduction, DeNoise by Acon Digital fits the bill nicely.
It analyzes background noise and utilizes subtractive gain adjustments, filtering and gating to clean up noisy recordings.
The simple interface makes it easy to compare before and after results. Advanced controls let you tweak the processing but good results come quick with the presets.
DeNoise also removes clicks/pops, adds natural noise generation, and links channels for stereo tracks. Straightforward and effective!
[Get DeNoise](https://acondigital.com/products/de noise)
10. Adobe Audition Noise Reduction
The Noise Reduction effect in Adobe Audition provides capable broadband noise cleanup right within the popular Creative Cloud suite.
It analyzes a selected region to build a noise profile, learning the acoustic signatures. Once processed, Audition applies frequency-based gain reduction to suppress the noise across your entire track.
You can capture noise samples from within your project clips or use entirely separate files. Adjustable controls help target the reduction to the specific noise in your recording.
While not as powerful as more advanced solutions, Audition brings efficient noise reduction to common video workflows.
How Much Noise Reduction Is Too Much?
When cleaning up noisy audio, it‘s easy to get overzealous and remove too much natural texture. Here are some signs you‘ve gone too far:
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Source audio starts sounding muffled and unnatural
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Attacks transient punch is dulled
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High frequencies get muted
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Structured reverb tails are diminished
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Intelligibility of speech is reduced
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Stereo image depth decreases
The best noise reduction breathes clarity back into the audio without undermining tonality and dimensionality. Dial back the reduction strength if the source audio becomes compromised. Finding the right balance takes practice.
Some tools like iZotope RX Advanced include spectral recovery to restore damaged harmonic content after heavy noise reduction. This can help maintain audio fidelity.
When to Just Re-Record Rather than Reduce Noise
Despite the great noise removal tools available, sometimes re-recording from scratch is better than trying to salvage a poor recording:
- If noise is at a similar volume level as the intended audio
- For variable background noise like traffic, talking, etc.
- If excessive clipping or distortion occurred during recording
- When miking technique can be greatly improved
It takes considerable time and effort to rescue an audio recording with major fundamental issues. Starting fresh often saves headaches in the end.
That said, many noisy recordings can be restored to sound great with surgical noise reduction and repair. It just requires finding the right tool and method for the specific audio issues at hand.
Conclusion and Recommendations
Whew, that was a lot of info! Here are my key tips to recap:
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Use proper mic technique and recording practices to minimize noise from the start
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For serious restoration work, invest in a professional platform like iZotope RX
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Try heavy-duty tools like Acon Digital Acoustica or Sound Forge for efficient noise removal
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Open-source Audacity provides a free starting point for DIY noise reduction
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New AI-powered solutions like Accusonus ERA work noise reduction magic automatically
With some diligence, you can salvage even noisy recordings and give them new life! I hope this guide provides everything you need to clean up your audio tracks and take your productions to the next level.
Let me know if you have any other questions. I‘m always happy to chat more about audio production and editing techniques!
