Compressor
Select the entire audio file
Compressor Effect Settings:
Threshold -12dB
Noise Floor -40dB
Ratio 2:1 for most jobs
Attack 0.20 secs
Release 1.0 (decay}
Tick Make-up gain for 0 dB after compressing
Alternate settings as follows:
Select the entire audio file
Threshold: -30 dB
Noise Floor: -50dB
Ratio: 5:1
Attack Time: 0.10 secs
Release Time: 1.0 secs
Tick Make-up gain for 0 dB after compressing
Another alternate compressor setting
Threshold = -18db
Noise Floor = -40db
Ratio = 2.5:1
Attack Time = 1.81 secs
Release Time = 11.1 sec
Noise Reduction (dB) Start at 30 dB and adjust as necessary. Keep as low as possible.
This setting controls how many dB’s Audacity will reduce your noise by. 30 dB is a good place to start. If in a controlled recording environment, a lower number like 10 or 15 dB might work. In a noisier situation, try a higher number like 35 or 40 dB.It’s good practice to keep this number as low as possible, because Audacity attempts to remove noise from the entire track, including spoken sections. The higher the number, the more likely it will be that Audacity will reduce non-noise sounds- like speaking- from your content.
Sensitivity (dB) start at 4.00 dB and adjust as necessary. Keep as low as possible.
This setting tells Audacity how aggressively to remove the noise, even at the risk of removing audio that isn’t noise. I like to think of this number as being equal to the size of a bull in a china shop. In this example, the china shop is the “good” parts of your recording, so even though you’ll probably break some amount of china by removing noise, you want to keep the damage (and therefore the bull) as small as possible.
As with the previous setting, keep this number as low as possible. Sometimes I’m able to get away with 0.00 dB, but I’ve also had to go as high as 10 dB. If you find yourself consistently using a number higher than 2 dB, it’s probably because you aren’t close enough to your microphone, resulting in a bad signal to noise ratio. Get closer to your mic!
Frequency smoothing (Hz) Just always use 6.
Frequency smoothing reduces artifacts resulting from noise reduction on low bitrate mp3s. If you hear these artifacts in your file, bump the number up until they’re gone
