Definition of a baffled plate in the context of sound radiation

[doofusdoggy]

Hi everyone, I've been reading quite a few papers on the study of sound radiation, and a common system that is studied is described as a "baffled plate". What exactly are the boundary conditions on a baffled plate? I thought it was simply that the edges have a pinned boundary condition, i.e. there can be no displacement but they can have slope. However in some papers it seems to mean a clamped boundary condition. I cannot find a definition anywhere. Could anyone give me a definitive answer please? Thanks

 

[Illmatic1]

.A baffled plate is a system where the edges of the plate are fixed to a framework, usually using screws or nails. This creates an enclosed space within the plate which can be used for acoustic purposes. The boundary conditions on a baffled plate depend on the type of plate being used and the type of analysis being done. In general, the most common boundary conditions are pinned (no displacement) or clamped (displacement is limited).