cheer(N)

function cheer(N)
%sound function, numericall simulation of a repeated chirp  
%cheer(N) repeats single chirp N times, default N=3

%V.Pastushenko, 6.th Feb. 2008

if nargin<1
    N=3;  
end

s=[];
M=round(1000*(.6+.4*rand(1,N)));
for i=1:N
    wid=M(i);
x=(0:wid)';
s=[s;sin((pi/wid)*x).^3.*sin(2*(x+x.^2/M(i)))];
end
sound(s/2);