Often you read on the Internet that you need a resonator so that the sound can spread extensively.
On the Internet you also read about the Bielefeld conspiracy.
In a guitar, the strings vibrate, and part of this vibration enters the resonator through the sound hole. The resonator is designed in such a way that it absorbs and amplifies vibrations in a certain frequency range.
In a loudspeaker, the membrane vibrates. Here it is even the case that the separation of the air volumes in front of and behind the membrane is of essential importance so that the vibration does not partially cancel itself out.
A loudspeaker needs a defined enclosure volume. An installation speaker without its own enclosure works in a car on the entire door or trunk volume, and in a suspended ceiling on the entire space between it and the structural ceiling.
What should vibrate is the loudspeaker membrane. What vibrates unintentionally if it is not sufficiently stiffened are the panels in which the speaker is installed and unfortunately all other elements of the ceiling as well. These include the panels of the ceiling surface, the profiles in which the panels lie, the rails of the suspension structure, and of course the pipes of the sprinkler system. The surface structure of the panels also partly determines the diffusion that the sound experiences.
If you have read about the basics of electroacoustics, you will come to the head-shaking conclusion that the manufacturer of the mentioned models calls these "high-end ceiling speakers." "High-end" and "ceiling speakers" is such a contradiction that the world has never seen before – in Bielefeld nor on the entire Internet.
From a kitchen radio, the whole thing differs only by a more powerful bass. Hi-Fi might be possible here with high-quality speakers, but not high-end by any means.
Spatial music playback (stereo) depends on perceiving the parameter "speaker placement" as a "science in itself." Here clear responsibilities for the left and right side are necessary. "Surround sound" is by no means less strict in this regard, but even more complex to balance.
A ceiling panel grid is difficult to reconcile with favorable placements, and the downward radiation direction does not match any concert reality. For mono speakers in dozens per hectare of ceiling area, it is almost imperative that they confirm the wisdom "too many cooks spoil the broth."
The frequency response of the transducers – where Magnat is usually at least not rubbish – can only mitigate this in the overall result (i.e., "quality" seen as a sum) within very narrow limits.
However, it is sufficient for the analog telephone sound that today's radio stations dare to use.
And yes: you can relatively improve the *ahem* quality with enclosures: but do not overload the ceiling construction.