PZM mounting and waterproofing

I’ve acquired four PZM-30Ds which I intend to mount on 1-meter square plex panels to form a cube. I intend to first record some Texas thunderstorms to see just how accurate a surround recording can be. 

Do the mics need to be acoustically coupled with the plex? Can I use Velcro between the mics and the plex to hold them, or will it compromise the bass? Second,how much rain they can take? I’d certainly attempt to shield them, but Texas thunderstorms have a way of getting into everything. 

Reply: Using Velcro to hold the PZMs will not compromise the bass. The Velcro should be thin so that the spacing between the PZM plate and the plex is as small as possible. Otherwise the PZM might develop a rough frequency response in the upper midrange.

The PZM-30D is not designed to handle water. Some outdoor recordists put an umbrella covered with felt over the microphones. The felt reduces the tapping sound of the rain on the umbrella. Another method of waterproofing is to put the PZM in a thin plastic sandwich bag. The bag should be limp, not stretched.