I set this up the way every honest review of it should start: by laying out twenty-two drivers across my living room and feeling slightly like I'd cheated. The bar is wide. The sub is heavy. The wireless rears want outlets within a reasonable walk of the listening position. Twenty minutes after I powered everything on, I watched the opening of Top Gun: Maverick and forgot I was reviewing a soundbar.
What the Q990D gets right is the channel count is real. The rear speakers are not virtualized; they are speakers, behind you, doing the thing speakers do. The eight-inch wireless sub is bigger than most soundbar subs and delivers the kind of low end where you don't have to imagine the explosion. SpaceFit Sound Pro ran a calibration sweep in three minutes and produced a noticeably better balance than the default — I've been burned by auto-calibration before, and this one earned its keep.
The meaningful 2024 upgrade is HDMI 2.1 with 4K/120Hz passthrough. If you own a PS5 or an Xbox Series X, you can route the console through the bar without the TV downshifting to 60Hz, which the previous Q990C couldn't do. Game Pro mode lights up the up-firers as environmental channels, which on something like Returnal is genuinely effective and on a turn-based RPG is a placebo. Either way, it's a feature gamers can actually use rather than a checkbox.
The ecosystem play is the catch. Q-Symphony, which adds the TV's own speakers to the soundbar's array, only works with a Samsung TV. The wireless Dolby Atmos pass-through that skips HDMI altogether also wants a Samsung set on the other end. Outside that ecosystem, you lose some of the headline integration, and a Sonos Arc Ultra or a real separates rig starts looking better.
The other catch is the price ladder. MSRP is $1,999. The previous-generation Q990C is still on shelves, frequently discounted to around $1,400, and delivers roughly ninety-five percent of the experience for thirty percent less money. The HDMI 2.1 passthrough is the one thing the C cannot match. If you're a console gamer who cares about 120Hz, the D is the only answer. If you're not, the C is the smarter buy and the harder one to feel bad about.
The footprint is real. The bar runs wide and deep — it visually wants a 55-inch TV minimum to look right, and on smaller sets it dominates the credenza. Setup of all the satellite pieces is not hard but is not fast: pair the sub, pair the rears, run calibration, plug in the consoles, walk the app through its setup, then realize the rears need a firmware update. Budget an hour. The form factor is also identical to the previous generation, so the upgrade is invisible to anyone who walks into the room.
Verdict: Buy this if you own a Samsung TV, you have a PS5 or Series X, and you want the closest thing to a true surround system in a soundbar box. If you don't need 120Hz passthrough, save the difference on the Q990C.