  Using the phenomenon of extraordinary sound transmission (EST) through
artificially constructed density-near-zero (DNZ) materials, we propose an
alternative approach to realize a very robust acoustic cloaking, which includes
one absorber and one projector connected by an energy channel. The elementary
unit cell is made of one single-piece homogeneous copper, but it well maintains
both the original planar wavefront and the nearly perfect one-dimensional
transmission, in the presence of any inserted objects. Furthermore, the overall
cloaked space can be increased, designed, and distributed by arbitrarily
assembling additional DNZ cells without any upper limit in the total cloaking
volume. We demonstrate acoustic cloaking by different combinations of DNZ cells
in free space as well as in acoustic waveguides, which enables any objects
inside the cells imperceptible along undistorted sound paths.
