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How to Fix Messy Audio: Video Edition

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To Fix Messy Audio, Video editing packages come equipped with various plugins that can bring great results, when used correctly.

There’s no magic wand waving when it comes to audio post production – The golden rule is to ‘get right at the source’, that is, try to record your source audio as best you can during the shoot.

However, when re-recording is simply not an option, post production can do amazing things to clean, smooth and enhance your scene’s sonic landscape.

Step 5. Crop Your Audio (frequencies)

Don’t use a tonne of different plugins in any random order. Audio degrades rapidly when pushed and pulled to extremes, much more so than video. Under-process (rather than over-process) in post and you’ll discover that with just a few plugins in your chain you can fix messy audio very quickly.

Recordings, sound effects, ADR or Foley can feel bloated and ‘boomy’ when frequencies below 200Hz are left untreated. Crop your audio inwards in order to expand what’s pleasant to your ears.

1 Insert an EQ on your audio channel, or set up your in built channel EQ
2 Cut all frequencies below 20Hz by engaging the ‘High Pass‘ control.
3 During playback slowly sweep the control upwards to 100Hz.
4 Listen for a lighter sensation – a clarity in the audio due to it being less ‘boomy’
5 You might stop at 40Hz or even 60Hz, 80Hz, 110Hz or around 200Hz.
6 If the sound is thin, pull the control back down to reintroduce low frequencies

Step 4. Know What You’re Dealing With: Use an Audio Analyzer

When the eye aids the ear you can be more sure of what you’re doing, what you’re seeing aligns with what you’re hearing.

We need to find out what frequencies make your audio messy and what clicks and pops and handling noise occupy what sonic space (what problem frequencies).

1Insert an Audio Analyser into your project master output and individual channels
2During playback of your low quality clip or sequence watch the graphical display
3Lead with your ears and follow with your eyes
4Many Analysers have a ‘Freeze’ function. This button will freeze the graphical display
5‘Freeze’ displays a snapshot of the frequencies present at that instance in time
6During playback quickly click ‘freeze’ when you hear a distracting unpleasant sound.
7If you see a very sharp peak at 3,100Hz (3.1kHz) then this is your ‘harsh’ sound
8If you see a large peak at 250Hz, this can sound ‘muddy’ or ‘messy’ or ‘boxy’
9If you don’t have a freeze function, use your eyes to pinpoint large peaks
10Once you’ve identified problem frequencies are you can begin correcting them

Step 3. Low / Low Mid / High Mid / Hi

Before you home in on the most obvious messy clips, or offending parts of a longer waveform then the rule of thumb is often this: use broad, subtle sweeps and peaks when cutting frequencies to generalise and not scrutinise your audio correction.

fix messy audio video NLE EQ
1Insert a parametric EQ onto your audio channel or clip
2Think of your audio in 4 quarters – ‘Low’, ‘Low-Mid’, ‘High-Mid’ and ‘High’
3Apply the frequencies you discovered in the audio analysis above to the tips below
4Many Analysers have a ‘Freeze’ function. This button will freeze the graphical display
5Select a ‘Low‘ EQ band and set a -3dB cut. e.g. Cut -3dB @ 60Hz
6Select a ‘Low-Mid‘ band and set a -3dB cut @ 250Hz
7Select a ‘High-Mid‘ band and set a -3dB cut @ 3,000Hz (3kHz)
8Select a ‘Hi‘ band and set a -3db cut @ 16,000Hz
9Use your ears and your OWN audio analysis to select EQ frequencies to process
10The last step is to use the output gain on the EQ plugin to give back audio level
11.Set the EQ plugin output gain somewhere between +1.5dB and +3dB

Step 2. Clicks and Pop

To fix messy audio video editors are often bundled with at least one Equalisation plugin. With some subtle Eq’ing now applied to your audio channel you can focus your attention on clicks, pops and audio noise.

To successfully fix messy audio video editing techniques are very similar to audio editing techniques. Techniques such as deNoise, deClick, Noise Gate are common but also ambience, reverb, width control and other mastering tools can be used.

1Use your eyes. Zoom into the waveform and look for sharp spikes and peaks
2Surgically remove clicks and pops by slicing offending sections out completely
3Use third party audio editing software to process clicks and pops externally
4If the clicks are too frequent, consider using dePop and deClick plugins
5Noise gating can help to control the ambient room sound of an audio recording

Encourage Experimentation

If you’re set on damage control and are determined to bring your recordings up to an improved quality then experimentation, as well as trial and error, is recommended.

EQ and Compression are your main tools, while audio analyzers, noise reduction and noise gates are allied to those tools. For me, audio analyzers allow for a great amount of accuracy when pinpointing sonic deficiencies that are not obvious to the ear right away.

I hope this article brings you closer to fixing messy audio and lays out some of the tools that make approaching audio with analytical ears easier and more intuitive – Let us know how it works out for you!