CEDAR Duo – declickle and auto dehiss
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Modern interpolators are based on signal modelling. By analysing the signal over a region of
several milliseconds the algorithm can build a model of the underlying signal and use the
information to replace each click with an interpolation that fits this model.
Crackle
Unlike a standard declicker, Declickle is able to detect high density, low amplitude, short
duration ticks within the signal.
This type of small impulsive disturbance is the cause of several common signal defects. If the
disturbances are randomly distributed, the degradation will sound like crackle or a 'chip-fryer'
type of noise. If they are regularly spaced, the degradation will sound like a buzz. Alternatively,
if they are correlated with the signal, the degradation will sound like distortion. Declickle will
correct all of these problems, so the term 'crackle removal' is slightly misleading.
There are other types of distortion (such as tape saturation) that Declickle does not address.
This is because these distortions are not caused by short-duration impulsive disturbances, but
by other defects that Declickle is not designed to detect.
