-- Butterworth BPF
-- Sampling Frequency =   44100.0
-- cutoff1 =    2000.0
-- cutoff2 =    5000.0
-- Order = 3rd
-- Quantized by 15 [bits]
-- **** 1st biquad ****
     a0_A <= "0011111111111111" when sw0 = '0' else "0000101101100011";
     a1_A <= "0000000000000000" when sw0 = '0' else "0000000000000000";
     a2_A <= "0000000000000000" when sw0 = '0' else "1111010010011101";
     b1_A <= "0000000000000000" when sw0 = '0' else "0101011100001110";
     b2_A <= "0000000000000000" when sw0 = '0' else "1100111111111010";
-- **** 2nd biquad ****
     a0_B <= "0011111111111111" when sw0 = '0' else "0000110101101011";
     a1_B <= "0000000000000000" when sw0 = '0' else "0000000000000000";
     a2_B <= "0000000000000000" when sw0 = '0' else "1111001010010101";
     b1_B <= "0000000000000000" when sw0 = '0' else "0111001010101000";
     b2_B <= "0000000000000000" when sw0 = '0' else "1100100000000100";
-- **** 3rd biquad ****
     a0_C <= "0011111111111111" when sw0 = '0' else "0000101101101011";
     a1_C <= "0000000000000000" when sw0 = '0' else "0000000000000000";
     a2_C <= "0000000000000000" when sw0 = '0' else "1111010010010101";
     b1_C <= "0000000000000000" when sw0 = '0' else "0101111010000000";
     b2_C <= "0000000000000000" when sw0 = '0' else "1101011011011000";