Denoiser controls in Final Cut Pro for Mac
Denoiser offers the following controls.
To add the Denoiser effect to a clip and show the effect’s controls, see Add Logic effects to clips in Final Cut Pro for Mac.
Main controls

- Threshold slider and field: Set the threshold level. Signals that fall below this level are reduced by Denoiser. 
- Reduce slider and field: Set the amount of noise reduction applied to signals that fall below the threshold. When reducing noise, remember that each 6 dB reduction is equivalent to halving the volume level (and each 6 dB increase is equivalent to doubling the volume level). - Note: If the noise floor of your recording is very high (more than −68 dB), reducing it to a level of −83 to −78 dB should be sufficient, provided this doesn’t introduce any audible side effects. This effectively reduces the noise by more than 10 dB, to less than half of the original (noise) volume. 
- Noise Type slider and field: Determine the type of noise that you want to reduce. - A value of 0 equals white noise (equal frequency distribution). 
- Positive values change the noise type to pink noise (harmonic noise; greater bass response). 
- Negative values change the noise type to blue noise (hissy tape noise). 
 
- Graphic display: Shows how the lowest volume levels of your audio material—which should be mostly, or entirely, noise—are reduced. Changes to parameters are instantly reflected here. 
Smoothing controls

- Frequency knob and field: Adjust how smoothing is applied to neighboring frequencies. If Denoiser recognizes that only noise is present on a certain frequency band, the higher you set the Frequency parameter, the more it changes the neighboring frequency bands to avoid glass noise. 
- Time knob and field: Set the time required by Denoiser to reach (or release) maximum reduction. This is the simplest form of smoothing. 
- Transition knob and field: Adjust how smoothing is applied to neighboring volume levels. If Denoiser recognizes that only noise is present in a certain volume range, the higher you set the Transition parameter, the more similar-level values are changed, in order to avoid glass noise. 
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