OneOdio OpenRock S2: Two minute review

I’ve tested so many of the best open earbuds recently that they’ve almost started to blur into one, but I’ve never forgotten two of the first open-ears I tested for how unique they were. One of these was the OneOdio OpenRock S – and it has finally seen a successor in the OneOdio OpenRock S2. But the thing is, it’s quite a different proposition.

The OpenRock Pro and OpenRock S were pretty big and bulky open-ears compared to what we’re seeing in 2025 but they were perfect for outdoor adventures or running thanks to their absolutely huge battery life, rugged design and solid, robust, inflexible design.

For better or worse the OpenRock S2 aren’t like the first-gen model but keep closer to current market trends in terms of design and feature set. I can’t say I’m not disappointed, but these new buds could be more appealing to a wider audience so I can understand the change.

These are slightly more affordable alternatives to most of the other major open earbuds we’ve seen this year, the majority of which sit just north of the $100 / £100 / AU$200 price line. I’d recommend them to people who want decent open-ears but don’t need the very best audio, fully-rounded feature set or long-lasting batteries.

The S2 are lightweight buds with a more flexible design and much smaller carry case, so won’t take up so much space in your bag or on your head than the last-gen model. I did find that this design presented a few issues with fit though, as the buds would sometimes move position on my head or get stuck on my ear’s antitragus, and I found myself missing the older buds’ design.

Another downgrade is a battery life in that it's roughly half that of the predecessors, but other areas compensate: OpenRock finally has a phone app for its earbuds, which wasn’t the case upon the release of the previous-gen buds.

The sound profile is warm with a clear focus on bass, with tech from the company emphasizing bass not to give it extra oomph, but to ensure you can even hear it in this form factor (which often loses it). They’re good options if you’re looking for something to work out with.

If you were put off by the original OpenRock’s rugged, chunky look and huge carry case, thinking it a bit too much of a fringe option for you, you’ll definitely think the S2 an interesting new pair of earbuds. But if those traits were the entire selling point of the originals for you (as they were for me), the S2 just don’t have that uniqueness.

OneOdio OpenRock S2 review: Specifications

OneOdio OpenRock S2 review: Price and availability

• Released in June 2025
• Costs $98.99 / £79.99 / AU$154

The OneOdio OpenRock S2 went on sale in June 2025, officially marking the second generation of OpenRock’s sports-specific open-ear headphones.

You can pick up the buds for $98.99 / £79.99 / AU$154 , so they’re cheaper than their predecessors, which released in October 2023 for $99 / £89 (roughly AU$150) although price cuts have seen the OpenRock S go for half that.

That also puts the OpenRock S2 as some of the most affordable open earbuds to come out this year, a good option for cost-cutters. You can find some competitors below, but let me speak plain: the options worth buying are all about $130 / £100 / AU$200.

OneOdio OpenRock S2 review: Design

• Small and lightweight case
• Lightweight buds, slightly wobbly design
• Hard-to-press physical buttons

Having tested previous OpenRocks, I was expecting a similarly huge carry case (relatively – earbuds cases can be like boxes of dental floss now) for the S2, but I was pleasantly surprised. It’s a much smaller pebble-shaped holder which weighs just 58g and easily fits in a hand.

While it’s made from a fairly brittle plastic that doesn’t feel like it’d survive much of a battering (I didn't try any drop tests), the speckled pattern on it makes it more distinctive-looking than the vast number of its rivals I've used.

The earbuds themselves are also smaller and more svelte than previous offerings from the company. They weigh just 7g each and are made up of a small bud, a thin rubbery sports loop and a larger counterweight/battery pack that sits behind your ear.

As stated, I’ve tested loads of open-ears and these have got to be some of the most comfortable, thanks to how small and lightweight they are. Often I’d completely forget I was even wearing them.

Despite being comfortable, the fit isn’t reliable, likely due to just how thin, flexible and wobbly the sports loop is. When running, working out or sometimes even walking, the driver housing near my ear would wobble or change position a little, which can have a big knock-on effect on audio quality.

Another thing to criticize on the design front is the touch controls. On-ear controls, be they touch capacitive sensors or physical clicking buttons, are a hard thing for companies to get right, but the S2 is possibly the worst example yet on an open earbuds design.

The button is on the bottom of the counterweight, so if you want to pause your music, you have to press upwards — which shoves the thing straight out of your ear. Now that’ll stop your music! The solution is to hold the bud in place with your other fingers or hand to keep it in place, but this is a much more convoluted process than, say, picking up your phone and pressing ‘pause’.

• Design score: 3.5/5

OneOdio OpenRock S2 review: Features

• 8-hour battery, 32 hours from case
• New app with extra features
• Reliable connection via Bluetooth 6.0

OpenRock has seriously cut the S2’s battery life from its predecessor, which is a big shame. You’re now looking at a lasting power of 8 hours per bud, or 32 hours when you factor in the case, which is about average for open-ears but far short of the 19/60-hour life of the OpenRock S. It’s a shame to see a downgrade like this from one of the S’ best selling points.

As with most open earbuds, there’s no noise cancellation here; in fact, the form factor makes it easy to hear surrounding sounds. In truth, the buds’ relatively low max volume means that often, you might not even hear your music over the surrounding din in built-up cities, say.

The OpenRock S2 work alongside the OpenRock phone app which brings a few extra features. The most important one of these is the equalizer, which has three presets (Rock Mode, Relax Mode and Boom Mode, a graphic of the equalizer curve being the only way you’ll know what any of them do) and a seven-band custom mode.

This was a little infuriating to use as every time you change profile, music quickly flickers off and back on, so repeatedly tweaking the sound creates a strobe-like effect.

The app offers a few premium features like Spatial Sound, a way to adjust the left-right balance of music, a Hi-Res Mode and Multi-Point Connection. Some expected features appear like the ability to customize touch controls and there are two rarer ones: the ability to set an alarm to let you know you’ve been listening for a set amount of time, and a maximum volume limiter (ironic, given what I said about the volume).

Throughout testing, I found the OpenRock S2 quick and easy to connect to my phone, and reliable at maintaining a connection.

• Features score: 4/5

OneOdio OpenRock S2 review: Sound performance

• 14.2mm driver
• Bass tech returns for warm sound profile
• Low max volume, can be hard to hear

Each bud of the OpenRock S2 has a 12mm driver. It supports LDAC, AAC and SBC codecs, the former once you enable it via the app. The buds sound decent for their cost, though they’re not the best open-ears for audiophiles.

A selling point of OpenRock’s first-gen open-ears is back here: TubeBass, which boosts low-end sounds to fix a common complaint of the form factor, that thumping rhythms can be lost in the gap between earbud and ear canal.

TubeBass works well in ensuring the S2 is one of the better open-ears for bass fans, ensuring that you hear the bump of a bass guitar, synth or double bass in your chosen song. It makes the buds useful for people who listen to lots of workout songs, though obviously they don’t compare to any over-ear or in-ears which will deliver far more bass.

The bass isn’t overwhelming though, so it doesn’t drown out the treble in sounds. The overall sound profile of the buds is undeniably warm though, so guitars are crunchy and brass can be punchy but vocal lines lack some sparkle and sharpness through the upper mids and trebles. Mids can also be lost in songs, even rockier ones that enjoy extra ‘oomph’ from their rhythm guitars.

The soundstage is fairly limited, combining instruments into a bit of a thick lump at times, but this isn’t as damning as it sounds because the kind of nuance that a detailed soundstage can offer can also be quickly lost in open-ears when surrounding sounds get in the way.

• Sound performance score: 3.5/5

OneOdio OpenRock S2 review: Value

OpenRock’s decision to price these as more affordable than most other open-ears from major brands was a smart one. It makes them tempting as an alternative to top options from brands like Nothing, Huawei and Honor, for people who want to save money.

The S2 isn’t so fantastic value for money that it’s an instant must-buy, but they still provide lots of bang for your buck. That’d be doubly true if a discount ever comes to them to reduce the price a little further, especially for US buyers.

• Value score: 4/5

OneOdio OpenRock S2 review: scorecard

OneOdio OpenRock S2: Should you buy them?

Buy them if...

Don't buy them if...

Also consider

How I tested

The OpenRock S2 underwent roughly two weeks of testing in order to write this review, and as the introduction implies they're just the latest in a long chain of open-ears I've been testing.

During the review period the buds were connected to an Android smartphone and I generally used them for music on Spotify but also occasionally for calls, games, TV show streaming and listening to voice notes. This took place on runs, at the gym, on walks around my neighborhood and at home.

I've been reviewing gadgets for TechRadar since early 2019 and have used a huge range of tech. This includes other open-ear buds as well as past earbuds from OpenRock and other headphones from parent company OneOdio.

Read more about how we test

• First reviewed: July 2025