This chapter presents the results of the tests conducted on the vibrations and acoustics test stand described in Chapter 3. The purpose of this chapter is to present and compare the vibration and structure-borne acoustic test results for a plate with and without smart damping. This chapter also discusses the benefits of smart materials when added to existing damping materials, as well as the weight benefits due to smart damping. The tests were designed to compare the smart damping materials with existing damping in terms of vibration and structure-borne noise reduction. Figure 5.1 illustrates the different test plate configurations used to evaluate the benefits of smart damping. The ‘undamped plate,’ which is untreated, is the standard plate that was used for the baseline test. The ‘shunted plate’ refers to the undamped plate with shunted PZTs. As such, the ‘unshunted plate’ is the undamped plate with PZTs attached to it, but without the shunt circuits. Sections 5.1 and 5.2 compare the undamped plate to the shunted and unshunted plates. The ‘damped plate’ refers to the test plate treated with passive damping materials, while the ‘shunted damped plate’ is the damped plate with the shunted PZTs. The benefits of adding shunted PZTs to damped plates are investigated in Sections 5.3 and 5.4. Section 5.4 compares the shunted plate to multiple damped plates to assess the damping benefits of smart materials with respect to added weight.