SOUNDPROOFING DEVICE HAVING INSERTS MADE OF A SOUNDPROOFING MATERIAL

An acoustic attenuation device having two inserts made of acoustically absorbent material, the two inserts being different from each other and being separated from each other so as to delimit between them a longitudinal slot, each insert including a front surface intended to be oriented towards a space to be acoustically attenuated; and two support elements which are made of substantially acoustically impermeable material and which at least partially delimit an internal cavity in which the two inserts are disposed, each support element including a cover part partially covering the front surface of a respective insert such that the front surfaces of the two inserts are partially exposed, the two cover parts delimiting at least one passage opening which emerges into the internal cavity and which is located at least partially opposite the longitudinal slot so as to clear an access to the longitudinal slot.