Question

MATLAB. Design your own low-pass shelving filter which can boost the low frequency of given music signal. After designing filter, apply the filter to the original music signal and observe the result. Include following plots.
A. Magnitude and phase plot of your filter.
B. Magnitude plot of original signal
C. Magnitude plot of filtered signal

Answer 1

close all,
clear all,
clc,

f = fdesign.parameq('F0,BW,BWp,Gref,G0,GBW,Gp,Gst',...
0, 0.3, 0.2, 0, 4, 2, 3.5, 0.5);
h = design(f);
hfvt = fvtool(h,'Color','white');
set(hfvt,'Filters',h);
legend(hfvt,'Lowpass Shelving Filter');

ProjectPath=pwd;
filename = strcat(ProjectPath,'\Sample.wav');

[x, Fs, nbits] = wavread(filename);
subplot(3,1,1); plot(x);
title('Original Sample.wav File Plot');
%soundsc(y,Fs);
y = filter(h,x);
subplot(3,1,2); plot(y); grid on, ylim([-3,3]);
str = strcat('Filtered InputSignal, Fc = ',num2str(Fc),' Hz'); title(str);

Magnitude Response (dB) Lowpass Shelving Fiter 0.F 0.2 0.9 Normalzed Frequency (x rad/sample)

Original Sample.wav File Plot 0.2 -0.2 10 040 x 10" Filtered InputSignal, Fc -0 Hz 10 10*