How We Research
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want active noise cancelling, deep bass and app-based tuning for everyday listening, choose CMF BY NOTHING Buds 2a; if you need an open-ear fit that keeps your ears free and your surroundings audible during runs, rides and gym sessions, choose Gelecek Bone Conduction Open-Ear.
• CMF BY NOTHING Buds 2a — biggest strength: 42dB hybrid active noise cancelling paired with a 12.4mm bio-fiber dynamic driver, so it's built for immersive, bass-forward listening in noisy places.
• CMF BY NOTHING Buds 2a — biggest trade-off: It's an in-ear bud, so it physically blocks your ear canal. If you want to hear traffic, gym announcements or a training partner, that seal works against you.
• Gelecek Bone Conduction Open-Ear — biggest strength: The hook-style open-ear design transmits sound through your cheekbones and leaves your ear canal completely unobstructed, so ambient awareness is the whole point.
• Gelecek Bone Conduction Open-Ear — biggest trade-off: No noise cancelling at all, and a 12-hour recharge time. It's not a headphone for a quiet, isolated listening session.
• Who each pick is for: CMF Buds 2a for commuters, call-heavy workdays and anyone who wants ANC and EQ control. Gelecek for runners, cyclists and gym-goers who prioritize safety and comfort over isolation.
The CMF Buds 2a is a closed, in-ear design with a clear purpose: shut the world out and make what you're playing sound big. The headline spec is the 42dB hybrid active noise cancelling, and that number matters in real life. On a bus, in an open-plan office or on a plane, ANC is the difference between hearing your podcast and hearing everything else. The 12.4mm bio-fiber dynamic driver is co-tuned with Dirac, and the description leans hard into "warm soundstage, rich mids and crisp, thundering bass." If you mainly listen to hip-hop, EDM or any bass-heavy genre, that's the profile you want.
The feature list is unusually deep for this class. Quad HD ENC mics with "Clear Voice Tech" and "Wind Noise Reduction 2.0" target call quality — genuinely useful if you take meetings outdoors. Bluetooth 5.4 adds a secure connection plus Google Fast Pair and Microsoft Quick Switch, so hopping between a laptop and a phone isn't a manual re-pair every time. Battery is rated at 8 hours per bud and 35.5 hours with the case, with a quick-charge that gives up to 2 hours of playtime from a 5-minute top-up. Full charge takes about 89 minutes. There's IP54 water resistance, a lanyard-ready case, and touch controls backed by the Nothing X app, which is where you get custom EQ profiles, adjustable ANC levels including a transparent mode, dual-device connectivity, a find-my-earbuds function and a low-lag gaming mode.
Who should buy it: commuters, students, remote workers, and anyone who wants one pair of buds that handles music, calls and noise in equal measure. Who should skip it: cyclists, runners on open roads and anyone who needs to stay aware of their environment. The in-ear seal that makes ANC work is exactly what you don't want when safety depends on hearing what's around you. Also worth noting — the app extras like ChatGPT voice access work through pairing with Nothing or CMF phones, so that particular feature isn't universal across all devices.
The Gelecek is a completely different animal, and that's the point. Instead of pushing sound into your ear canal, it sits on your cheekbones and transmits vibration through bone. Your ears stay open. The claimed benefit is that you hear music and your surroundings at the same time — and for anyone who runs, cycles, walks busy streets or trains in a shared gym, that's not a gimmick, it's the reason to buy this style at all.
The design details support that use case. It's an open-ear hook shape in Porcelain Grey, and the hook form factor is what keeps it stable during movement without cramming anything into your ear. It's rated IPX5, so sweat and light rain are handled. Bluetooth 5.4 matches the CMF on the connectivity generation, and battery life is rated at 8 hours — the same as the CMF's per-bud figure, though there's no charging case here to extend it. The bone conduction driver is the only driver type listed, and the brand claims a fully enclosed cavity design that reduces sound leakage by up to 50%, which matters if you don't want everyone around you hearing your playlist.
Here's the honest trade-off. There is no noise cancelling — the "noise control" field is listed as None. That's not a defect, it's the design philosophy: open-ear headphones can't isolate you from the world because isolating you is the opposite of what they're for. The other spec that stands out is the 12-hour charge time, which is long. Plan on charging it overnight rather than topping it up in ten minutes. There's also no app, no EQ customization and no touch-control ecosystem mentioned — you get the headphone, an adapter, and that's the package.
Who should buy it: runners, cyclists, gym-goers, outdoor walkers, and anyone who has ever felt unsafe wearing sealed earbuds near traffic. Who should skip it: anyone who wants to block out noise on a commute, wants heavy bass, or wants app-level control over how their music sounds.
Side-by-Side: Which Should You Choose?
• Best for bass and sound customization → CMF BY NOTHING Buds 2a. The 12.4mm dynamic driver plus Dirac tuning plus custom EQ in the app.
• Best for situational awareness and outdoor safety → Gelecek Bone Conduction Open-Ear. The open-ear, bone-conduction design is built specifically so you can hear traffic and surroundings.
• Best for total battery runtime → CMF BY NOTHING Buds 2a. 35.5 hours with the case versus 8 hours standalone. If you hate charging daily, the case wins.
• Best for fast top-ups → CMF BY NOTHING Buds 2a. A 5-minute charge returns up to 2 hours of playtime, versus a 12-hour full charge on the Gelecek.
• Best for calls → CMF BY NOTHING Buds 2a. Four mics with ENC, wind noise reduction and voice clarity processing.
• Best for gym and sweat exposure → Gelecek Bone Conduction Open-Ear. IPX5 and a hook design that doesn't rely on an ear-canal seal.
• Best for a minimal, no-app setup → Gelecek Bone Conduction Open-Ear. Nothing to configure, nothing to install.
If I had to pick one, I'd buy the CMF BY NOTHING Buds 2a. In my opinion it's the more versatile product by a wide margin — ANC, a bigger driver, four mics, a charging case that nearly quintuples your runtime, quick charge, IP54 and a genuinely useful app all point to a headphone you can wear all day in almost any situation. The Gelecek does one thing well and does it honestly: keep your ears open while you move. But that's a narrower job. Unless open-ear awareness is your specific, non-negotiable requirement, the Buds 2a covers more ground. Before you decide, check the current price on Amazon for both — the value math depends on what each one costs you today.
For most people, yes — it has active noise cancelling, a larger dynamic driver, four call mics, a charging case with 35.5 hours of total battery and app-based EQ. The Gelecek wins only if open-ear awareness is your priority.
They're a different listening experience. Bone conduction transmits through your cheekbones and leaves your ear canal open, so you lose the sealed-in bass and isolation that in-ear buds like the Buds 2a deliver. You gain awareness of your surroundings instead.
The Gelecek Bone Conduction Open-Ear, in my opinion. Its IPX5 rating, hook design and open-ear fit are made for movement, and you can hear what's happening around you. The Buds 2a is IP54 and in-ear, which is fine for indoor training but blocks outside sound.
Yes — Bluetooth 5.4 supports dual-device connectivity, plus Microsoft Quick Switch and Google Fast Pair. That makes switching between a laptop and a phone much smoother than re-pairing each time.
The CMF Buds 2a charges fully in about 89 minutes, and a 5-minute quick charge gives up to 2 hours of playtime. The Gelecek lists a 12-hour charge time, so it's best charged overnight.
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