HW1 ECE301S11 Kyle Haver - Rhea

Smoke on the Water MATLAB Code

%% Beat Length
deltat = 0.00005;
beatlength = 60/112;

%% Note Lengths
Qnote = 0:deltat:beatlength;
Enote = 0:deltat:(beatlength/2);
Hnote = 0:deltat:(beatlength*2);
DQnote = 0:deltat:(beatlength*1.50);

%% Frequencies
fA = 440;
fG = (2^((-2)/12)) * fA;
fBf = (2^(1/12)) * fA;
fC = (2^(3/12)) * fA;
fDf = (2^(4/12)) * fA;

%% Notes
qG = sin(2*pi*fG*Qnote);
hG = sin(2*pi*fG*Hnote);

qBf = sin(2*pi*fBf*Qnote);

dqC = sin(2*pi*fC*DQnote);
hC = sin(2*pi*fC*Hnote);

eDf = sin(2*pi*fDf*Enote);

%% Play Tunes
tune = [qG qBf dqC qG qBf eDf hC qG qBf dqC qBf qG];

% Regular Speed
sound(tune, 1/deltat)

% 2X Speed
% half beatlength
beatlength = beatlength/2;
Qnote = 0:deltat:beatlength;
Enote = 0:deltat:(beatlength/2);
Hnote = 0:deltat:(beatlength*2);
DQnote = 0:deltat:(beatlength*1.50);
qG = sin(2*pi*fG*Qnote);
hG = sin(2*pi*fG*Hnote);
qBf = sin(2*pi*fBf*Qnote);
dqC = sin(2*pi*fC*DQnote);
hC = sin(2*pi*fC*Hnote);
eDf = sin(2*pi*fDf*Enote);

tune = [qG qBf dqC qG qBf eDf hC qG qBf dqC qBf qG];

sound(tune, 1/deltat)

% X(2t)
% half beatlength and double frequency
qG = sin(2*pi*2*fG*Qnote);
hG = sin(2*pi*2*fG*Hnote);
qBf = sin(2*pi*2*fBf*Qnote);
dqC = sin(2*pi*2*fC*DQnote);
hC = sin(2*pi*2*fC*Hnote);
eDf = sin(2*pi*2*fDf*Enote);

tune = [qG qBf dqC qG qBf eDf hC qG qBf dqC qBf qG];
sound(tune, 1/deltat)

Sound File: File:Kyle H Smoke on the water.wav

Hidden Backwards Message

The message that is repeated forwards is "number 9" accompanied by instrumental music. There is no discernable message in the reversed sound file.

MATLAB CODE

[y, Fs] = wavread('Beatles.wav');
sound(y, Fs)
x = flipud(y);
sound(x, Fs)
wavwrite(x, Fs, 'Kyle_H_reverse.wav')

Sound File: File:Kyle H reverse.wav