The system analysis of the MIMO optimal feedback quantization used to produce switching signals is proposed here. The switching signals are then fed into the switch mode power amplifier to drive actuator array. The architecture of the power amplifier used in this paper allows the sharing of switching elements among actuators and is different from the traditional one-to-one method in actuating a large number of devices. To actuate all of the devices at the same time, the MIMO optimal feedback quantization generates control signals optimally basing on minimizing the weighted measure of quantization error. The discussion on bounding the system states under the zero initial conditions is made. The result tells that the stability can be achieved by limiting the maximum amplitude of inputs when the MIMO system has stable zeros. To simplify the computational complexity of quantization, a sub-optimal method for actuating three-actuator system is mentioned. A design example of 2-input 2-output system which is applied to the class-D stereo audio amplifier (dual actuators) is addressed. The control performance and cross-talk behavior are investigated.