timeLength = 6                        # seconds
fs = 44100
t = np.arange(0, timeLength, 1.0/fs)


# EXPCHIRP -----------------------------------------

t1 = np.arange(1, timeLength+1, 1.0/fs)
A = np.e**-t
f0 = 2000.0                                     # Hz
f1 = 10000.0
k = (f1/f0)*(1/t1)
phi0 = np.pi / 2                                # phase, radiants.                                                 # sampling rate
s0 = A * np.sin(phi0 + 2*np.pi*f0*((k-1)/np.log(k)))