function v1 = relatflt(dB1,dB2)
%relatflt(dB1,dB2) len=7 FIR filter of response:
% 0 dB gain at f0 = 1/2
% dB1 = gain compensation in dB at f1 = 1/4
% dB2 = gain compensation in dB at f2 = 3/4
g1 = 10^(dB1/20); % convert dB gain to linear
g2 = 10^(dB2/20); % convert dB gain to linear
a = (g1-g2)*0.37117514279802; % 3sqrt(2)/8 - 1/2/pi
b = (g1+g2)*0.25 - 0.5;
c = (g1-g2)*0.01762175220474; % sqrt(2)/8 - 1/2/pi
d = (g1+g2)*0.5;
v = [c b a d a b c];


function v2 = flt15(dB1,dB2,dB4,dB5)
%flt15(dB1,dB2,dB4,dB5) len=15 FIR filter response
% dB1 = gain in dB at f1 = 1/6
% dB2 = gain in dB at f2 = 2/6
% 0 dB gain at f3 = 3/6
% dB4 = gain in dB at f4 = 4/6
% dB5 = gain in dB at f5 = 5/6
g1 = 10^(dB1/20); g4 = 10^(dB4/20); 
g2 = 10^(dB2/20); g5 = 10^(dB5/20);
a0 = 0.27883*(g1+g5) + 0.25000*(g2+g4) -0.05767;
a1 = 0.15735*(g1-g5) + 0.27254*(g2-g4);
a2 = 0.19550*(g1+g5) -0.39100;
a3 = 0.01301*(g1-g5) + 0.02254*(g2-g4);
a4 = 0.02883*(g1+g5) - 0.05767;
a5 =-0.08647*(g1-g5) + 0.18169*(g2-g4);
a6 =-0.02725*(g1+g5) + 0.12500*(g2+g4) -0.19550;
a7 =-0.04486*(g1-g5) + 0.09085*(g2-g4);
v =[a7 a6 a5 a4 a3 a2 a1 a0 a1 a2 a3 a4 a5 a6 a7];