% Question 1: function[] = question1() N1 = sin(2*pi*391.995436*[0:0.0001:1]); %G quarter note N2 = sin(2*pi*466.1637615*[0:0.0001:1]); %Bflat quarter N3 = sin(2*pi*523.2511306*[0:0.0001:1.5]); %C dotted quarter N4 = sin(2*pi*391.995436*[0:0.0001:1]); %G quarter N5 = sin(2*pi*466.1637615*[0:0.0001:1]); %Bflat quarter N6 = sin(2*pi*554.3652618*[0:0.0001:0.5]); %Csharp eigth N7 = sin(2*pi*523.2511306*[0:0.0001:2]); %C half
rest = [0:0.0001:2.5]; %rest half and an eigth
% smoke on the water (part a): tune = [N1 N2 N3 N4 N5 N6 N7 N1 N2 N3 N2 N1 rest]; wavwrite(0.02*tune, 18667, 'question1a.wav'); % twice as fast (part b): wavwrite(0.02*tune, 37333, 'question1b.wav');
% y(t) = x(2t) (part c):
newtune = [1:1:(length(tune)/2)];
for i=1:(length(tune)/2)
newtune(1,i) = tune(1,2*i);
end
wavwrite(0.02*newtune, 18667, 'question1c.wav');
Sound files: Media:question1a.wav Media:question1b.wav Media:question1c.wav
% Question 2:
function[] = question2()
[y, Fs] = wavread('Beatles.wav');
y = flipud(y);
wavwrite(y, Fs, 'question2.wav');
Sound file: Media:question2.wav
1. The repeated phrase was "number nine". 2. I couldn't hear any message in the reversed version.
