Object Based Audio is just techy way of describing the likes of Dolby Atmos and similar systems.  We're all familiar with the standard surround-sound, based on speakers situated in a circular configuration at screen height (ideally, but in practice these days the speakers tend to be on two flat planes, situated front and rear).  OBA takes it further by introducing speakers above head height (mainly in the ceiling) to provide a third dimension to the sound.

object based audio

In fact, whilst the idea isn't exactly new (I remember cinemas in the analogue days siting speakers in a similar configuration) the advent of the latest technology, driven by Dolby does make for an immersive experience.

In the end, its all a matter of creating a suitable balance so it may not easily be a DIY option but I can see it being used in many of our installations from now on.