“Multiband (also spelled multi-band) compressors can act differently on different frequency bands. The advantage of multiband compression over full-bandwidth (full-band, or single-band) compression is that unneeded audible gain changes or “pumping” in other frequency bands is not caused by changing signal levels in a single frequency band.” Wikipedia

*Unofficial documentation

source: http://en.wikipedia.org/wiki/Dynamic_range_compression#Multiband_compression

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