Dolby ATMOS, Auro and DTS-X use algorithms designed to envelop the home theater listener with sound coming from above the listener. All of these formats are modeled on the latest “object-based” sound systems and sound tracks that have been developed to provide the audience with a totally immersive sound field.
The IC-6-OBA from Atlantic Technology contains a high dynamic range 6-inch woofer coupled with a pair of one-inch tweeters designed to produce a “wide scatter.” Most other in-ceiling designs tend to have a narrow dispersion and can create audible “hot spots” to listeners directly the below the speakers. By contrast, the Atlantic IC-6-OBA spreads out the sound field similar to what is actually heard in movie theaters where elevation speakers are usually 30 to 40 feet above the listener. They also incorporate circuitry to protect the tweeters from high voltage spikes.
I recently worked on a system that employed these as ceiling speakers. Their dispersion and frequency response were excellent. It is not documented, but the tweeters can be aimed by pressing on the outside edge of the tweeters.
These speakers are reasonably efficient at 88db/watt and retail for $325.