My favorite Meta Quest 3 accessory just got an audio upgrade — and VR never sounded better

Leave it to Kiwi Design to deliver another valuable upgrade to Meta Quest 3 and Quest 3S headsets, this time bringing immersive audio to VR in a comfortable battery head strap.

The company behind the quintessential VR accessory that I won't use my Quest 3 without, the H4 Boost Halo Battery Strap, now has the Kiwi Design K4 Duo. It's an all-in-one audio head strap with battery, and it solves an issue I've had with Meta's headsets: loud audio.

Yes, the Quest 3 and 3S offer great 3D spatial audio, but when I'm playing games, watching movies or even listening to tunes while connected to Windows 11 in VR, sound leaks out for all to hear. That's no longer the case when the K4 Duo is strapped on, as its adjustable, cushioned earphones deliver isolated, clear audio — just like what the best gaming headsets do.

Throw in the nearly 3-hour battery life to extend VR sessions (like the H4 Boost), 45W dual-port fast charging and comfortable, flexible design, and you've got yourself a head strap that adds premium trimmings to any Quest 3 headset.

It's not without some flaws, but it's one of the best Meta Quest 3 accessories you can get to upgrade your VR sessions. Read on to find out why.

Kiwi Design K4 Duo Audio Head Strap: Cheat Sheet

• What is it? An all-in-one audio head strap with battery for Meta Quest 3 and Quest 3S VR headsets.
• Who is it for? Quest 3 and 3S owners after extended battery life (without being connected to a cable) and headphones in a secure, comfortable head strap.
• What does it cost? The Kiwi Design K4 Duo is priced at $159 at Amazon in the U.S. and £139 at Amazon in the U.K. However, you'll often find it for $139/£129, and even less (down to $109/£109).
• What do we like? Its adjustable, lightweight fit, the clear surround sound audio from its cushioned earphones, additional battery life and fast dual-charging system.
• What don’t we like? At full price, it's on the expensive side, and ears can get hot after longer VR sessions due to the sponge foam pads.

Kiwi Design K4 Duo Audio Head Strap: Specs

Kiwi Design K4 Duo Audio Head Strap: The ups

Kiwi Design's K4 Duo isn't too different from its H4 Boost Halo head strap, especially when it comes to its core principles like its comfort and extra battery life. That's no bad thing, but this has the addition of fine-tuned audio from its attached earphones.

What VR should sound like

Finding out the K4 Duo comes with its own audio put me in two minds: having a head strap deliver a set of headphones is a smart move, but would it be just a cheap add-on, especially considering they kind of look like the sponge-foam headsets you'd get on a flight?

Rest assured, they aren't. As soon as I attached the head strap and plugged in the well-sized USB-C cable to my Meta Quest 3, I could immediately hear the difference in soundscape compared to the VR headset's speakers. Even on the homescreen, where I have the gushing noise of a fountain and birds chirping every once in a while, the audio was finely tuned.

Even at full volume, sound didn't leak from the earphones when I took off the headset. That's great news for VR owners who need to game quietly or those who want to be fully absorbed by the best Quest 3 games out there. And that's especially true of all the music-based rhythm games like Beat Saber, Pistol Whip or Smash Drums.

Thanks to the switch on the right earphone, I could switch between the earphone audio and the Quest 3's own speakers easily, too.

Speaking of, I decided to dive back into Batman: Arkham Shadow, and as I was preying on thugs and grappling between ledges, I could hear the "zip" and "ting" of the clasp attaching to a point and pulling me in. I also heard each "thud" of my fist connecting to foes while beating them up, which was satisfying, indeed.

For a more immersive, spooky feel, I put on Metro: Awakening. As with the spatial audio of the Quest 3's speakers, I could clearly hear the disturbing whispers of ghosts crying for help around me, along with chats from enemies in the distance as I slowly crept my way around them. I was also freaked out by the fast pitter-patter of a mutated spider crawling on me (shudder-inducing stuff).

It also makes for more isolated listening when watching shows on streaming apps like Netflix or Amazon Prime Video, which was great when watching the final episodes of "Squid Game" season 3. While not quite the all-encompassing cinema-sounding levels, it's still nice to get the big-screen treatment with loud audio with clarity.

With the Meta Quest 3S Xbox Edition now out, it also means the head strap can deliver this excellent audio to the latest Xbox Game Pass titles, and that includes AAA games like Doom: The Dark Ages. Now, I wouldn't say it matches the audio quality of the best headsets for gaming around, as there aren't any customizable EQ settings or high-end drivers, but it's fully immersive nevertheless.

Overall, for completely inclusive sounds for your VR sessions, the K4 Duo's earphones will do the trick.

Find your fit

As with the H4 Boost Halo, the K4 Duo matches its comfort and easy adjustability but takes it a step further with its simple padded top strap, flexible earphones and lightweight feel.

That last one is surprising, as the K4 Duo weighs 16.1 ounces compared to the H4 Boost's 15.7-ounce weight. This is more due to the K4 Duo's lack of a front facial headpad, which I noticed felt heavier on the head. It trades it for a silicone-added top strap instead, which I found to be very comfortable on my scalp.

The audio head strap is also supremely easy to put on and adjust, thanks to the rear dial that can change the tightness.

It's also flexible to adjust the angle when putting it on or taking it off, all so I could easily slip my head into the strap and get into VR. That customizable fit is also easier on the face, so the Quest 3's facial interface isn't squashing to the areas around my eyes that can irritate the skin.

Finally, the earphones themselves are also flexible, so they can be folded in and out, swivel to the sides and adjust for length. That makes it a head strap size for all.

More time in VR

I've said it before, but the Quest 3 and Quest 3S' 2-hour battery life just isn't long enough for the many VR games and apps that demand more time to use. That's what the H4 Boost solved, and the K4 Duo does exactly the same.

Using the same 20.4 Whr / 5,300 mAh battery capacity, my Meta Quest 3 could last nearly 3 hours longer with the head strap plugged in. That's a boon to anyone who wants to play in VR for that much longer, or actually watch a full-length movie without the headset dying on you.

It also comes with the same dual-port fast charging, which simultaneously charges the K4 Duo and Quest 3/3S. So, with a 45W charger, both devices get 22.5W each. It takes a little over 2 hours to charge them from 0% to 100%, which is just as long as Meta's VR headsets. Again, you're getting up to 5 hours of battery life in a single charge instead of just a measly 2 hours.

Kiwi Design K4 Duo Audio Head Strap: The downs

The Kiwi Design K4 Duo does a lot right, but you'll be paying more for this VR upgrade over other head straps out there, including the companies own H4 Boost Halo battery strap. That, and its earphones can be a tad irritating during long VR sessions.

More than most

Priced at $159 / £139, the K4 Duo is Kiwi Design's most expensive head strap to date. It makes sense, considering it comes with earphones, padding and that extra battery capacity, but it's more costly than the H4 Boost ($99 / £79) and BoboVR S3 Pro ($89 /£76). Even the Meta Quest Elite Strap with battery ($129/£129) is more affordable.

Again, these don't come with their own headphones, and the thing is, Kiwi Design often offers significant discounts on its head straps. As of writing, the K4 Duo is down to $109/£109, which is far more enticing.

That's all to say that if you're looking to grab the K4 Duo, it's best to wait until it drops to its lowest price, especially during big sales events.

A tad toasty on the ears

With its sponge-foam padding on the earphones, the K4 Duo was immediately comfortable on my ears. It doesn't press too firmly on them either, giving my ears a nice cushion while I move around frantically in games like Batman: Arkham Shadow or Pistol Whip.

However, I noticed that after a few hours in a VR session, my ears were getting hot and irritated. Not majorly, mind you, but enough for me to fold the earphones out to give my ears a break. That's expected with this kind of material, but I wouldn't say it's a deal-breaker. But it would have been nice to see memory foam cups used instead, similar to the SteelSeries Arctis Nova 3.

Kiwi Design K4 Duo Audio Head Strap: Verdict

The Kiwi Design K4 Duo Audio Head Strap with Battery may only apply to a niche group of VR users that want more VR time on their Meta Quest 3 or Quest 3S with personal audio, but it does a fine job of executing its advantages.

Not only does it make the Quest 3 supremely more comfortable and secure to wear, but it also extends the Meta Quest 3's battery life to a more suitable time and delivers fantastic audio straight to your ears.

For those that already have a head strap and audio solution, such as the Final VR3000 wireless earbuds (£89) or Final VR500 wired earbuds ($35), then the K4 Duo's all-in-one perk won't be worth its price. Let it be known that its otherwise comfy sponge-foam earphone padding can irritate your ears after a long session, but that's only a small nuisance.

But for those who want to give their Quest 3 or 3S an upgrade that covers battery, comfort and audio, then make sure the K4 duo is at the top of your list of VR accessories to pick up.