My partner falls asleep at nine. I do not. The window between nine and eleven used to mean either headphones plugged into the TV via a cable that ran across the rug, or no TV at all. The Sonos Ace solved this in the most Sonos way possible: I tapped the side of the right cup, the audio from the Arc soundbar in the living room jumped over to my head, the speaker went silent, my partner kept sleeping, and I watched the back half of a movie. That feature alone is the reason to buy this headphone, and if you do not already own a Sonos soundbar, none of it applies to you.
The TV Audio Swap path is the genuinely new thing in the category. It currently works with the Sonos Arc and Arc SL, with the Beam and Ray promised in firmware. Latency is low enough that lips sync on a sitcom, and Dolby Atmos with head tracking is convincing on the kind of movie where things blow up behind your shoulder. None of the other ANC headphones in this price range do anything close, because none of the other ANC headphones in this price range are made by a company that already lives in your living room.
The noise cancellation is solid. Roughly 88 percent measured reduction, which puts it in competitive territory with the Bose QC Ultra and the AirPods Max, and it cuts a flight engine to a hum and an office HVAC to nothing. The eight beamforming microphones do enough work that calls are clean in normal rooms, although the noise rejection on a windy street is about average.
The sound is where the Ace is more divisive. The default tuning has a deep sub-bass shelf and a treble peak around 5 to 8 kHz that on long listening sessions starts to feel sharp. There is an EQ in the app, but it only exposes bass and treble sliders, with no presets and no parametric controls, which is a strange omission from a company that knows audio. After about a week I had settled the bass slider down and the treble slider down, and the headphone got noticeably more comfortable for daily use. If you mostly listen to bass-forward genres it will sound great straight out of the box.
Codec support is current. Bluetooth 5.4, aptx Lossless over Snapdragon Sound, AAC for iPhone, multipoint for two devices. Battery is 32 hours with ANC on, which beats every other premium ANC headphone I have used. A three-minute top-up gets you three hours, which is the kind of forgiving curve that matters when you are running out the door.
The complaints are real but mostly small. There is no IP rating, so these are not the headphones you take to the gym. The 312-gram weight is fine for hours but not all day, and the cups run small enough that anyone with larger ears will feel the edge of the pad on their ear rather than around it. The app is also the same Sonos app that controls your speakers, which means changing the EQ on the headphones involves navigating past your entire speaker collection.
The value math is simple. If you have a Sonos Arc or Beam, the Audio Swap is genuinely worth the premium and there is nothing else that does it. If you do not, the Sennheiser Momentum 4 is $50 cheaper with better battery and better sound, and the Bose QC Ultra has better noise cancellation for the same money.
Verdict: Buy the Ace if you own a Sonos soundbar and you have ever wished you could move the sound onto your head. Otherwise, get a Momentum 4 or a QC Ultra.