How to create a sound signal vector by appending a vector to another vector in Matlab? -

i'm trying create music piece appending 1 vector vector. create row vector , trying use sound(ct, 8000); play music, throws error cell contents reference non-cell array object. should do? code:

z = sin(0*pi*(0:0.000125:1)); g = sin(2*pi*220*2^(10/12)*(0:0.000125:0.25)); f = sin(2*pi*220*2^(8/12)*(0:0.000125:0.25)); eb = sin(2*pi*220*2^(6/12)*(0:0.000125:1)); d = sin(2*pi*220*2^(5/12)*(0:0.000125:1)); ct = [z g g g eb z f f f d]; sound(ct, 8000); 

what means?

cell contents reference non-cell array object