Denoiser is designed to reduce stationary noise, including broadband noise, in audio signals. Stationary noise can include tape hiss, microphone hum, power mains buzz, camera motor noise and other types of noise that do not change in level or spectral shape throughout the recording.
Denoiser can learn the type of noise you want to remove from the recording to give you the best results. To train Denoiser, identify a section of the recording that contains only noise, without any useful audio signal. Often these places are at the beginning or end of a file, but may also be during pauses or breaks in speech.
Select the longest section of noise you can find, then hit the Train button. This will "teach" Denoiser the noise profile of your file. In some cases you may not have a section of just noise, or you may want RX to find a quiet section for you. If this is the case, open the options menu next to the Train button (+) and choose Auto Train.
After the noise profile is captured, select the whole file that needs to be denoised. You can also make a time-frequency selection to denoise only certain frequency regions of the file.
If you are using the Simple panel, you can adjust the desired amount of Noise supression. If you are using Advanced panel, you can separately adjust amount of noise reduction for tonal and broadband parts of noise, and fine tune the noise reduction process with some additional parameters. To read more about Advanced parameters see this page .
Smoothing and Musical Noise Reduction
The Smoothing (Basic tab) and Musical Noise Reduction (Advanced tab) controls supress artifacts that result from removing broadband noise. These artifacts are sometimes described as "chirpy" or "watery" sounds left behind during the noise reduction process. Increase the Smoothing or Musical Noise Reduction parameter to reduce these artifacts.
Choosing an Algorithm
RX's Denoiser offers three algorithms that range in processing time. It is a good idea to start with Algorithm A, as it works very quickly. If you're not happy with the result, try B and then C, which will take longer to process but can yield better results. Algorithms B and C are fairly slow, and may not be able to preview in realtime. This is a good place to use the Compare Settings window to save time when comparing these options.
Read more about Denoiser controls in the Reference Guide.