A surgical system is provided having a console (100) that receives a cassette (10) with a rigid fluid channel (34) formed into a rigid plastic component or housing (14). The housing serves as a substrate for an elastomeric acoustic coupling (38) that can be formed on the housing outside of the fluid channel. An acoustic transducer (120) is elastically mounted within the console, such as by a spring (131), so as to apply a relatively constant force between the transducer and the acoustic coupling when the cassette is installed in the console.
