Resonator
The resonator makes it possible to use its support as emitter of the sound. That it is a shelf, a ceiling, a door, a partition. They are, for the most part, not suitable for glazed surfaces.

The resonator makes it possible to use its support as emitter of the sound. That it is a shelf, a ceiling, a door, a partition. They are, for the most part, not suitable for glazed surfaces.