Patent ID: 7676048

Claim:
A digital graphic equalizer, comprising: (a) a cascade of peak/notch filters F (1) , F (2) , . . . , F (N) where N is an integer greater than 1, and each of said filters has a transfer function which is a bilinear transform of an analog transfer function of the form (s 2 +2K 1/2 αω 0 s+ω 0 2 s 2 )/(s 2 +2K −1/2 αω 0 s+ω 0 2 s 2 ) with K a gain, α a positive constant, and ω 0 an analog center frequency; (b) wherein said center frequency corresponding to F (j) is equal to a band-edge frequency corresponding to F (j+1) and/or F (j−1) for j=1, 2, . . . N, and wherein α is the same for all of said filters.