In a filter device, a filter coefficient calculation circuit has a parameter table. The parameter table stores a plurality of sets of filter coefficients associated with a first parameter based on a frequency and a second parameter based on respective plurality of levels representing a degree of attenuation...http://www.google.fr/patents/US8067684?utm_source=gb-gplus-shareBrevet US8067684 - Filter device and electronic musical instrument using the filter device
Filter device and electronic musical instrument using the filter device
