burrow~ filtering burrow~ performs filtering much like drown~, but it utilizes a second signal input to utilize as a filter threshold reference. The threshold controls the extent of the filtering. It is specified in dB. Useful values lie in the range from 0 to -90 dB. Threshold inversion is available via the invert message.	from the library : FFTease Format : External Environment : msp / PD freeware Max 3.x / 4.x http://www.sarc.qub.ac.uk/~elyon/LyonSoftware/MaxMSP/FFTease/