Removing unwanted noise from a recording can be a tricky thing. It is not always we have the benefit of being in a perfect recording environment with perfect gear.
Try Multiband Compression/Expansion
How to use Waves C4 as a noise reduction tool.
The thing that bothered me with this recording was the high frequency noise. Listen carefully in the high frequency range.
You will need to use headphones to be able to hear what is going on in the video.
This is what the Waves manual says:
- Find a section of audio where only noise is present and loop the playback
- Listen to each band separately (using Solo) and determine the amount of noise reduction you want to apply to this band. Set Gain equal to the amount of noise reduction wanted in each band (a negative value)
- Set Range to exactly compensate for the gain reduction in low levels, that is the Range should be exactly the inverse of Gain. If Gain=-12dB the Range=+12dB
- While previewing the noise, set Threshold in each band such that it is just enough above the noise energy in this band, so that you hear enough noise reduction in that band
- It will be useful here to use a hard Knee setting (set the Knee control in the Master control section to its maximum).
Now preview an audio segment where the wanted signal is present, and make sure it is indeed enough above the threshold(s) so that no gain reduction takes place (the yellow line is at 0dB gain).
Pay attention to the problematic passages, where the signal fades out or other soft sections where the audio comes closer to the noise level; careful adjustment of Threshold is required there to avoid too much degradation of the signal itself.
Other Tools and Approaches
The C4 approach described above can be done with any multiband compressor as long as it has the capability to work in expander mode.
Try Logic Pro Multipressor
The idea here is to use it as a multiband expander rather than as a compressor.
You will need to use headphones to hear what is going on in the video.
- Turn compression off
- Make it a bit more Peak sensitive by lowering the Peak/RMS value, you will want the expander to respond rather quickly
- Adjust the Attack and Threshold in the Expander section
- Loop the noisy segment you want to filter out
- Solo and work with each frequency band in turn
- Set the Ratio and Reduction (-50 dB) in the Expander section to find the Ratio when the noise disappears
- Ease off the Reduction to a suitable level
- Go through each band in successive order
- Listen with the audio you want to keep and tweak the settings
- Try make Gain Change move towards 0 to let sound though
To me, it has been more difficult to get a satisfying results with the Multipressor compared with the Waves C4 method.
Reaper ReaFir Noise Reduction
Reaper has an interesting FFT Dynamic Processor plug-in called ReaFir that can be used for noise reduction.
The result is somewhat swooshy, as I have experienced with many other noise reduction tools.
A long time ago I tested Waves X-noise, with some good results but it is an expensive and specialized bundle. Also it created a lag in the system making it impossible to do live recornings. Another problem is that most noise reduction tools easily creates swooshy artifacts. For me, multiband compression/expansion works best and gives the least distortion of the sound.