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Chapter 12 Specialized 135
 Smoothing Transition knob: Adjusts how smoothing is applied to neighboring volume
levels. If the Denoiser recognizes that only noise is present in a certain volume range,
the higher you set the Transition Smoothing parameter, the more it also changes
similar level values to avoid glass 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, so keep an eye on it!
Using the Denoiser
Locate a section of the audio where only noise is audible, and set the Threshold value
so that only signals at, or below, this level are filtered out. Then start playback and set
the Reduce value as you listen to the audio, so that as much noise as possible is
reduced, but as little of the desired signal is reduced.
The Denoiser uses FFT (Fast Fourier Transform) analysis to recognize frequency bands of
lower volume and less complex harmonic structure, and then reduces them to the
desired dB level. In principle, this method is completely discrete, as neighboring
frequencies are also affected.
If you use the Denoiser too aggressively, however, the algorithm will produce artifacts,
which are obviously artificial and therefore less desirable than the existing noise in
most cases. If using the Denoiser produces these artifacts, you can use the three
Smoothing knobs to reduce or eliminate them.