Feed Forward System and Feedback System:The Basic Noise Control System

The present paper reviews on the basic noise control system i.e. feedforward system and feedback system. In applications of active noise control, the cancelling signal is generated electronically and introduced into the system using transducers such as loudspeakers that convert the electronic signal to sound. In many cases, the physical mechanism responsible for the reduction of the unwanted noise is a little more subtle than mere cancellation. In cases where cancellation is the only control mechanism, the noise level may be reduced at some locations, but will be increased at others so that the total energy of the unwanted noise and the cancelling sound is conserved.