enclosure for containing various mechanical operating parts of a domestic appliance such as a dishwasher is shown the enclosure 10 is limited by the space available as indicated above and depends on the space available for the appliance and the environment in which the appliance is to be placed the enclosure is provided with an acoustic absorbent material liner 26 as described above generally contacting the interior surface 30 of the enclosure 10 the mechanical components within the enclosure may take a variety of forms in fig1 the schematic representation of an electric motor 12 is shown having a sheave or pulley driving a pair of belts 13 and 14 which drive accessory components 16 and 17 a variety of the mechanical and control components may be contained throughout the enclosure and are schematically represented by elements 20 and 21 as indicated previously the complexity and number of mechanical components within the enclosure depend on the system 39 s application however in many applications a portion of the machinery or apparatus cannot be contained within the interior surface 31 of the acoustic absorbent material liner 26 for example the electric motor is shown having a component 24 that extends into the space normally occupied by the sound absorbing lining 26 similarly device 17 is required to be mounted close to the enclosure wall 11 thus requiring removal of a portion of the acoustic lining in either of the above cases an opening is provided in the acoustic lining to accommodate the extending parts however such openings permit the propagation of sound waves emanating from.