An acoustic barrier assembly for a vehicle and a method of manufacturing the same is disclosed. A decoupler layer surrounds a pass-through opening in a wall of the vehicle to defining a decoupler aperture that is open to the pass-through opening. A barrier layer abuts the decoupler layer and defines a barrier aperture that is also open to the pass-through opening. An acoustic seal is integrally formed in the barrier layer. The acoustic seal defines an exposed region of the barrier layer that is not bounded by the decoupler layer. The exposed region of the barrier layer directly contacts the wall around the pass-through opening and seals around a penetrating member that extends through the pass-through opening. The acoustic seal thus reduces flanking noise traveling through a gap between the penetrating member and the pass-through opening.