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clc
 
clc
 +
 
clear
 
clear
 +
 
% Part 1
 
% Part 1
 +
 
  x = 1;  
 
  x = 1;  
 
%initializes counter for iterations
 
%initializes counter for iterations

Revision as of 09:16, 19 January 2011

clc

clear

% Part 1

x = 1; 

%initializes counter for iterations for i = 1:1:3 %% a loop to perform three iterations for parts a,b,c

delta = 0.00005 ; %sampling rate

if x == 2

  bpm = 2*112  ; 

%beats per minute for parts a and c

else

   bpm = 112 ; 

%beats per minute for part b

end

bps = 60/bpm ; %beats per second

rest= 0:delta:3*bps; % there is a three beat rest at the end of the song

q = 0:delta:bps ; % length of a quarter note in terms of tempo

h = 0:delta:2*bps  ; % length of a half note in terms of tempo

e = 0:delta:0.5*bps  ; % length of an eighth note in terms of tempo

dq = 0:delta:1.5*bps  ; % length of a dotted quarter note in terms of tempo

if x==3 A_note = 2*440 ; %Pitch frequency for A4

G_note = 2^(-2/12)*A_note  ; %Pitch frequency for G

Bflat_note = 2^(1/12)*A_note  ; %Pitch frequency for B flat

C_note = 2^(3/12)*A_note  ; %Pitch frequency for C

Dflat_note = 2^(4/12)*A_note  ; %Pitch frequency for D flat

else %%changes the pitch by multiplying the A4 frequency by two

A_note = 440 ; %Pitch frequency for A4

G_note = 2^(-2/12)*A_note  ; %Pitch frequency for G

Bflat_note = 2^(1/12)*A_note  ; %Pitch frequency for B flat

C_note = 2^(3/12)*A_note  ; %Pitch frequency for C

Dflat_note = 2^(4/12)*A_note  ; %Pitch frequency for D flat

end


Gq = sin(2*pi*G_note*q) ; %% Standard function for quarter note, G pitch

Bfq = sin(2*pi*Bflat_note*q) ; %% Standard function for quarter note, B flat pitch

Ch = sin(2*pi*C_note*h) ; %% Standard function for half note, C pitch

Cdq = sin(2*pi*C_note*dq) ; %% Standard function for dotted quarter note, C pitch

Dfe = sin(2*pi*Dflat_note*e) ; %% Standard function for eighth note, D flat pitch


smoke_song = [Gq,Bfq,Cdq,Gq,Bfq,Dfe,Ch,Gq,Bfq,Cdq,Bfq,Gq,rest];

if x==1 sound(smoke_song, 1/delta); wavwrite(smoke_song,1/delta, 'normal_smoke_on_the_water'); elseif x==2 sound(smoke_song, 1/delta); wavwrite(smoke_song,1/delta, 'fast_smoke_on_the_water'); else sound(smoke_song, 1/delta); wavwrite(smoke_song,1/delta, 'highpitch_smoke_on_the_water');

end

x=x+1;

end


%%Part 2

[song, fs] = wavread('Beatles.wav'); %Original clip says 'Number 9' repeatedly

reverse = flipud(song);

sound(20*reverse,fs); %% could not hear the song so had to amplify it

wavwrite(reverse,fs,'reverse_Beatles') %reversed clip sounds like 'Let me on, Desmond' repeatedly

Media:normal_smoke_on_the_water.wav
Media:fast_smoke_on_the_water.wav
Media:highpitch_smoke_on_the_water.wav
Media:reverse_Beatles.wav

Alumni Liaison

Basic linear algebra uncovers and clarifies very important geometry and algebra.

Dr. Paul Garrett