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Asus makes a surprising variety of peripherals for a computer company, and the ROG Cetra Open earbuds I've been testing for the past month are perhaps the furthest away from their core gaming focus. Unlike most earbuds, which sit inside the ear canal to seal off the outside world, these ones are held externally and operate more like open-back headphones. It's a fascinating idea that I've not come across before, and it produces a wireless headset that is both comfortable to wear and convenient for interacting with the world around you.
I found the Cetra Open most useful when running, doing chores at home and playing games while listening for the doorbell. Of course, you can still use them as your primary headphones in other circumstances, but you have to be aware that the headset leaks sound in both directions by design. Thankfully, this only really applies if you have the volume set fairly high, so other people hearing your music is less of a concern than with full-size open-back headphones.
I appreciated the fact that the headset curves around the upper part of your ear with a flexible silicone hook, so it's easy to take them on and off, yet they remain in place even during intense exercise. There's a detachable (and reflective) neck strap in the box, but I didn't find it necessary. The design is lightweight too, at 11 grams, yet the headphones still manage to last for 16 hours with RGB disabled. The charging case extends total battery life in the field to 48 hours, and there's also a 2.4GHz USB-C transmitter (with USB-C passthrough) inside to make using the headphones easier (and lower latency) with PCs, gaming handhelds and so on.
The ROG Cetra Open stood up well to sweat and the occasional rain shower, and they're IPX5 rated for dust and water resistance - though the bulky charging case isn't equally protected. Usability is good too, with a physical button on each earbud to play/pause, skip tracks, activate your voice assistant or enter pairing mode. Customisation of these functions isn't possible, but the Gear Link web and mobile app does allow you to disable or adjust the RGB lighting, choose EQ settings and set gestures. It works well enough, though more customisation and better-explained settings wouldn't be unwelcome.
The downside here is that the audio quality isn't as good as you'd hope from a high-end in-ear headset. The 14.2mm "DLC" drivers are perfectly cromulent, but you do lack some of the low-end presence and overall detail of standard in-ears. It's hard to pick individual instruments out of a mix, for example, and I wouldn't trust these for pinpointing the sound of an enemy player's footsteps in tactical FPS games like Wardogs. Still, for non-competitive fare these are perfectly good, and I think sacrificing a bit of detail for the ability to carry on a conversation while gaming is completely justifiable.
At £185/$206, the ROG Cetra Open is a pricey set of wireless earbuds. It would be easy to say that you ought to get something more standard, like SteelSeries' Arctis GameBuds, which do much the same job at nearly half the price. Yet if you hate the feeling of in-ear headphones in your ears, or you want to be able to hear your surroundings, while still having that convenient pocketable form factor and full gaming credentials, what Asus has crafted here has real value. It's a big swing, but one that's well-executed and doesn't lack for refinement. Respect.