Nearly impossible

rectly through the barrier is significant in some cases. For example, with large angles of diffraction, the diffracted noise may be less than the transmitted noise. In this case, the transmitted noise compromises the performance of the barrier. It can be reduced with a heavier barrier. The allowable amount of transmitted noise depends on the total barrier attenuation needed.

The fourth path shown in Figure 6.7.2 is the reflected path. After reflection, noise concerns only a receiver on the opposite side of the source. For this reason, acoustical absorption on the face of the barrier can sometimes reduce this reflected noise; however, this treatment does not benefit receivers in the shadow zone.

In most practical cases, reflected noise is not important in barrier design. If the source of noise is represented by a line of noise, another short-circuit path is possible. Part of the source may be unshielded by the barrier. For example, the receiver might see the source beyond the ends of the barrier if the barrier is not long enough. This noise

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