Latest revision as of 09:04, 27 August 2010

HW1, ECE301, Prof. Boutin

In this homework assignment, we were asked to write a Matlab code to play the "Hail Purdue" song with different speeds and pitch.

%Emily Blount
%Homework 1
%September 4, 2008
%ECE 301, Mimi Boutin

%clear memory and console
clear;
clc;

%Part a: Playing Twinkle Twinkle Little Star (since I don't know Hail Purdue.)

% Note Frequencies
C = 261.626;
D = 9*C/8;
E = 5*C/4;
F = 4*C/3;
G = 3*C/2;
A = 5*C/3;
B = 15*C/8;
Chi = 2*C;

%Array of Notes for Song
S = [C, C, G, G, A, A, G, F, F, E, E, D, D, C]; 

%Time definition and Sampling Frequency
delta = 0.00005;
endtime = 0.5;
t = 0:delta:endtime;

%Playing the song
for x = 1:1:length(S)
    song = sin(2*pi * t * S(x));
    sound(song, 1/delta);
end

pause(5)

%Part b: Playing the song 2x faster
delta = 0.00005;
endtime = .25;
t = 0:delta:endtime;

%Playing the song
for x = 1:1:length(S)
    song = sin(2*pi * t * S(x));
    sound(song, 1/delta);
end

pause(5)

%Part c: Rescaling song to y(t)=x(2t)
delta = 0.00005;
endtime = 0.5;
t = 0:delta:endtime;

%Playing the song
for x = 1:1:length(S)
    song = sin(2*pi * 2* t * S(x));
    sound(song, 1/delta);
end
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