A:Answer Hi Sonyuser,
The system becomes a 5.1.4. The rear speakers add 2 height channels but are a duplicate of channels 4 and 5 that are in the soundbar.
The HT-A5000 envelops you in authentic 5.1.2ch surround sound with up-firing speakers, side beam tweeters, built-in subwoofers, and advanced technologies that bring you Dolby Atmos® and DTS:X® audio as well as 8K and 4K video passthrough. And with rear speakers it supports 360 Spatial Sound Mapping, taking movies, TV and music into a whole new realm.
-David