If you're wondering just when you can envelop yourself in Dolby Atmos sound at home, Denon is more than happy to tell you. The home theater firm says it will launch two Atmos-equipped AV receivers, the X4100W and X5200W, in the US this October. Neither will be cheap, as the bleeding-edge tech implies. For $1,399, the X4100W delivers Dolby's all-encompassing audio in up to a 7.1.2-channel setup (seven regular speakers, one subwoofer, two overhead); splurge on the $1,999 X5200W and you can add two extra speakers to the mix, whether they're on the ground or the ceiling. Either will bring the media support you'd expect for that kind of outlay, including 4K video processing and media sharing over AirPlay or DLNA. That's a lot of cash to shell out to add an extra dimension to your surround sound, but Denon is undoubtedly targeting very high-end living room setups -- if you didn't flinch at buying an expensive 4K TV, these receivers are for you.