In this video I show you the size of the AP AC EDU and also give a brief demo. This unit is very impressive. The diameter is ~12 inches and the depth is around 5 inches. It comes with an adhesive template for cutting the hole out of your ceiling tile. There are some undocumented features to the system, such as being able to connect to it with SIP. We will likely use this so we can page using the system from our existing phone system. Check it out, give a thumbs up and please subscribe!
http://community.ubnt.com/t5/UniFi-Updates-Blog/UniFi-4-8-18-is-released/ba-p/1555743
The link I provided above is the latest stable controller and you can use it to provision and use the EDU for playback.
That thing really amplified my gum chewing, SORRY!