Study on low-frequency broadband sound absorption based on an array of shunt loudspeakers

Low-frequency noise has the greatest impact on people’s physical and emotional health. The spatial dimensions impose limitations on the conventional passive sound-absorbing materials and structures. The shunt loudspeaker, which is comprised of a loudspeaker coupled to a shunt circuit, is a fast-emerging technique for controlling low-frequency noise. However, there have been few studies on the sound absorption of a shunt loudspeaker array, with current research primarily focusing on multi-frequency sound absorption. To solve this issue, this paper suggests a low-frequency broadband sound absorber on the basis of a shunt loudspeaker array. The suggested absorber’s model is based on the parallel equivalent impedance method. The shunt circuit settings for each unit can be designed relatively and independently. Each unit’s coupling effect can be used to provide outstanding low-frequency broadband acoustic absorption performance. The proposed low-frequency absorber does not need to rely on a large spatial size but rather on the design of the shunt circuit parameters of each unit. The feasibility of the proposed absorber is validated through numerical simulations employing both the parallel equivalent impedance method and the finite element method.