On my Denon receiver, it is an Atmos capable receiver (Denon X3700H) The zone two function enables multi speaker support in the main listening area. For example… And in my situation… Turning on zone two is essential to enable my overhead speakers. I don't spend a lot on speakers because I cannot afford, however, I was given a few sets of pretty decent Klipsch bookshelf speakers which allowed me to finally explore hooking up a pair of front height channels above my display. However, my receiver could not do this internally. I am able to hook up a 9.2.2 speaker configuration with the receiver, which is 2 (L & R) fronts, Sides and rear surround speakers 2 overhead and 2 subwoofers. In order to do this, I must turn on zone two in the receiver for the overhead ceiling speakers. When I added the two left and right front height speakers, I had to change my configuration in the receiver. I had to set the overheads to middle overhead instead of front overhead or back overhead. And then I could add the two front height channels. However, they had to be powered by an external amplifier, which, luckily I was able to secure. I've never used zone two in a multi room configuration as I need all of the speaker options in my main listening area for the best Dolby Atmos/DTSX listening experience. Just thought I would add this… It's a first world problem, but the listening area sounds much more flushed out now, and I can finally understand the benefit of front height speakers Once again, compliments on the article, very helpful and advise everybody to read, even if you're just interested in setting up a proper Dolby Atmos system at home