Revision as of 08:18, 4 September 2008 by Rwijaya (Talk)

Audio files

Normal Two times faster Higher pitch

MATLAB Code

%Ronny Wijaya
%rwijaya@purdue.edu
%ECE 301 HW 1

delta = 0.00005;

%Notes Freq. founded on http://en.wikipedia.org/wiki/Piano_key_frequencies

C2 = 523.251;

B1 = 493.883;
A1s = 466.164;
A1 = 440;
G1s = 415.305;
G1 = 391.995;
F1s = 369.994;
F1 = 349.228;

E1 = 329.628;
D1s = 311.127;
D1 = 293.665;
C1s = 277.183;
C1 = 261.626;

B0 = 246.942;
A0s = 233.082;
A0 = 220;
G0s = 207.652;

%Timing variations' definition
quarter=.25;
half=.5;
threequarters=.75;
one=1;
onehalf=1.5;
two=2;


%Notes we are going to play
notes=[A0,B0,C1s,D1,E1,F1s,F1s,G1,G1,G1,D1,E1,F1,F1s,F1s,F1s,E1,D1,E1,F1s,F1s,E1,B0,C1s,D1,C1s,B0,E1,A0,A0,B0,C1s,D1,E1,F1s,F1s,F1s,G1,G1,D1,E1,F1s,B0,F1s,D1,B0,A0,D1,F1s,A0,B0,F1s,E1,D1,D1];

%Timing variations we have
timing=[one,half,half,threequarters,quarter,half,half,half,quarter,quarter,half,quarter,quarter,onehalf,one,half,half,threequarters,quarter,half,half,half,quarter,quarter,half,quarter,quarter,two,threequarters,quarter,half,half,threequarters,quarter,half,quarter,quarter,half,half,half,half,two,threequarters,quarter,half,half,half,half,half,half,threequarters,quarter,threequarters,quarter,two,two];

for lcv=1:length(notes)
	t=0:delta:timing(lcv);
	a=sin(2*pi*t*notes(lcv));
	sound(a,1/delta);
end

for lcv=1:length(notes)
	t=0:delta:.5*timing(lcv); 
	b=sin(2*pi*t*notes(lcv));
	sound(b,1/delta);
end

for lcv=1:length(notes)
	t=0:delta:timing(lcv);
	c=sin(2*2*pi*t*notes(lcv));
	sound(c,1/delta);
end


wavwrite(a,'hw1.1 Ronny Wijaya normal speed.wav');
wavwrite(b,'hw1.1 Ronny Wijaya two times faster.wav');
wavwrite(c,'hw1.1 Ronny Wijaya two times frequency.wav');

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