CEDAR's uniquely effective debuzzing and hum removal capabilities in a simple rackmount module
"... it does a specialised job with an effectiveness and integrity that perhaps nothing else can match, and as such should become standard equipment in any facility that ever has to deal with this kind of problem seriously."
Studio Sound, July 1999.
The family of degradations known as buzz includes audio phenomena such as power supply hum, camera noise, and many of the unspecified buzzy audio degradations that affect OB and location recordings. Comb filters and parametric filters will remove some of these, but the side effects of echo, and a strongly coloured hollow nature are unacceptable. Furthermore, traditional techniques cannot adapt to variations in the buzz frequencies and will always damage the signal that coincides with the buzz harmonic frequencies.
The BRX+ debuzzer uses a buzz detection and removal technique based, in part, upon Baysian analysis, and this eliminates the unwanted side-effects introduced by simple filtering. The BRX+ will lock on to and track buzzes, successfully eliminating them even if the frequency drifts by as much as 0.5Hz at 50Hz. It will also rescue the signal that lies at the same frequencies as the buzz harmonics. The BRX+ is, therefore, particularly suitable for use by broadcasters, and in forensic audio laboratories where the reduction of these noises can increase the listenability of surveillance tapes, and assist transcription.