The opcode eqfil is a 2nd order tunable equalisation filter based on Regalia & Mitra
design (“Tunable Digital Frequency Response Equalization Filters”, IEEE Trans.
on Ac., Sp. and Sig Proc., 35 (1), 1987). It provides a peak/notch filter for
building parametric/graphic equalisers.

asig  eqfil   ain, kcf, kbw, kg [, iskip]

kcf  is the filter CF
kbw is the notch/peak bandwidth
kg is the filter gain, < 1 makes the filter a band reject (notch) and
> 1 creates a peak at the CF.

The filter response outside outside the bandwidth is flat.

Now in CVS (man page coming soon), will be in the next release.

Victor

Victor Lazzarini
Music Technology Laboratory
Music Department
National University of Ireland, Maynooth