The invention provides a thin
broadband sound-absorbing structure. The structure comprises a sound-absorbing material, a support and at least two
layers of
mechanical impedance plates, wherein the sound-absorbing material is installed on the inner side of one end of the support, a supporting plate is arranged on the inner wall of the other end of the support, each of the
mechanical impedance plates consists of a back plate and sticky elastic rings at two ends of the back plate, adjacent back plates are not in contact, sticky elastic rings are stuck to the supporting plate through an
adhesive, the sticky elastic rings, the support inner wall and the back plates are attached tightly, a hollow is formed among the sound-absorbing material and the
mechanical impedance plates, and the back plate on the outermost side is recessed towards the support end face by certain distance.
Mechanical impedance is coupled to a traditional sound-absorbing material and a
cavity resonance absorption mechanism, a novel thin
broadband sound-absorbing mechanism is formed, the structure thickness is not increased basically based on the acoustic performance, the middle / high-
frequency sound absorption performance is good, the low-
frequency sound absorption effect is improved greatly and the sound-absorbing structure of which the thickness is thin and the sound-absorbing
frequency band is wide is produced.