John Brandt

    RFZ floors are concrete all the time. 😉

    Membrane trapping I found are pretty tricky to implement as they should be installed in specific places, right?

    Yes, it is very important HOW they are built and where they are positioned. Membranes work in the pressure zone. You're familiar with the Crown PZM? PZM = Pressure Zone Microphone. You can make any omni, small-diaphragm microphone into a PZM by placing it about 1/8" (3 mm) from a boundary surface. Pointing directly at the surface.

    Right at the surface of a floor, wall, or ceiling particle velocity ceases and pressure begins. So... a membrane trap must be as close as possible to the pressure regions of your room.