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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want an app-tunable, IPX7 waterproof true-wireless set for music, calls and sweaty workouts, choose EarFun Free 2S; if you need earbuds that physically hook over your ears and stay put for running and long days, choose kurdene Earbuds.
• EarFun Free 2S — biggest strength: a 7mm composite dynamic driver, 4 microphones for calls, the EarFun App with multi-EQ and a low-latency game mode, plus IPX7 waterproofing and wireless charging.
• EarFun Free 2S — biggest trade-off: it's a rounded-tip in-ear design with no ear hooks, so the fit depends entirely on the eartip seal rather than any mechanical grip.
• kurdene Earbuds — biggest strength: an over-ear hook design with soft silicone ear hooks, a 16.1mm vibrating diaphragm driver, Bluetooth 5.4 and a 60-hour total playtime figure.
• kurdene Earbuds — biggest trade-off: no companion app, no custom EQ, no stated waterproof rating, and it's a plastic over-ear build — so tuning and water protection are what you give up.
• Who each pick is for: EarFun Free 2S for listeners who want to shape their own sound and don't mind relying on the eartip seal; kurdene Earbuds for runners, gym-goers and anyone whose earbuds keep working loose.
The EarFun Free 2S is a true-wireless in-ear set built around a 7mm composite dynamic driver. EarFun's own spec sheet frames it as a bass-forward tuning with detailed mids and treble, and the frequency range is listed at 20Hz–20kHz with 32 ohm impedance and 100dB sensitivity. In plain terms, that's an easy-to-drive driver that should hit hard low end without needing a headphone amp. If you like a warm, punchy sound on pop, hip-hop and podcasts, the design points that way.
The feature that separates it most is the EarFun App. Inside it you get multi-EQ adjustment, customisable touch controls, a battery readout and a game mode that lowers latency for video and mobile gaming. That's a real advantage if you're the type who wants to nudge the sound toward your taste instead of accepting one factory tuning. You can also disable the touch controls entirely if you keep bumping them by accident — a small thing that matters a lot day to day.
Around the outside, the Free 2S is IPX7 waterproof, which is the rating that makes sweat and rain a non-issue rather than something to worry about. It charges over USB-C or wirelessly, runs Bluetooth 5.2, and each bud weighs about 3.99g. Battery is listed at up to 7 hours per charge. For calls, there are 4 microphones aimed at pulling your voice out of background noise.
Who should skip it: if your ears have never held a rounded-tip in-ear securely, or you want a mechanical hook holding the bud in place, this isn't the shape for you. There's no ear hook here — the fit is the seal and nothing else.
kurdene Earbuds: Who It's For
The kurdene Earbuds take a different approach entirely: they're over-ear sport buds. Instead of sitting in the bowl of your ear and hoping the tip seals, the design rests on top of your ear and is held there by soft silicone ear hooks. That's the whole pitch — "snug and stable," in kurdene's words, for workouts and everyday wear. If your history with earbuds is one of them popping out mid-run, this is the shape that solves it.
The driver is a 16.1mm vibrating diaphragm, a much larger figure than the Free 2S's 7mm, and kurdene describes the tuning as powerful bass, crisp mids and clear treble. Bigger diaphragms generally move more air, which is how the low end feels fuller at lower volumes. It also lists built-in microphones that isolate your voice for calls. Impedance is 32 ohm and the frequency range is quoted as 20Hz–20,000Hz.
Battery is the headline: up to 12 hours of continuous playtime per charge, plus 48 more from the charging case, for a 60-hour total. That's a large number for anyone who dislikes charging routines. Connectivity is Bluetooth 5.4 with a stated range of up to 33 feet (10 metres), which is the current generation and should mean stable audio/video sync for gaming and movies. The case charges in about an hour, and the box includes three pairs of earplugs in S, M and L, plus a fast charging case and cable. Each bud weighs 3.2 ounces.
Who should buy it: runners, gym users, cyclists, warehouse and site workers — anyone who needs the bud to stay put and last a long shift without a recharge.
Who should skip it: if you want to fine-tune your EQ, switch on a low-latency game mode, or have a stated waterproof rating, the kurdene doesn't offer those. There's no app, and no IP rating is listed.
Side-by-Side: Which Should You Choose?
• Best for staying in your ears during running → kurdene Earbuds. The over-ear hooks and soft silicone grips are a mechanical fit, not a seal-and-hope fit.
• Best for sound customisation → EarFun Free 2S. The EarFun App gives multi-EQ, custom touch controls and a game mode. kurdene has no app.
• Best for water and sweat protection → EarFun Free 2S. IPX7 is an explicit rating; kurdene lists no IP rating at all.
• Best for call clarity outdoors → EarFun Free 2S. Four microphones are dedicated to voice pickup and background rejection.
• Best for the newest Bluetooth generation → kurdene Earbuds. Bluetooth 5.4 versus the Free 2S's 5.2, with a stated 33-foot range.
• Best for charging convenience → EarFun Free 2S. It supports both USB-C and wireless charging; kurdene's case charges over cable only.
• Best for bigger drivers and a fuller low end at low volume → kurdene Earbuds. A 16.1mm diaphragm versus a 7mm driver.
In my opinion, I'd buy the EarFun Free 2S for everyday listening, commuting and calls. The app-based EQ and touch customisation, the 4-mic setup and the IPX7 rating give you more control over how the buds sound and where you can wear them, and that's worth more to me than raw battery hours on a normal day.
I'd only switch to the kurdene Earbuds if my real problem is fit — if buds fall out when I move. The over-ear hooks, the 60-hour total playtime and Bluetooth 5.4 make it a purpose-built sport pick, and for running and long shifts that trade-off makes sense.
Check the current price on Amazon before deciding — both are budget-friendly designs, and the final call usually comes down to fit versus features.
FAQ
how to make wired earbuds stay in ear
The same principle applies to any bud that sits inside your ear canal: the seal is what holds it. Try the different eartip sizes you have — the kurdene set includes three pairs in S, M and L — and pick the largest one that still feels comfortable. A tip that fills the canal without pressure grips far better than a loose one, which is why rounded-tip designs like the Free 2S live or die on tip choice.
Pull the top of your ear gently up and back to straighten the canal, then seat the bud so the tip points slightly forward and down into it, and let it settle. For an over-ear design like the kurdene Earbuds, the bud rests on top of your ear and the silicone hook loops behind it — so you're positioning the hook, not pushing the tip deep. Release the ear and check that the bud doesn't shift when you turn your head.
how to keep earbuds in ears
For in-ear buds, a proper seal plus the right tip size is the whole answer, and keeping your ears clean of excess wax helps the tip grip. For over-ear buds, the hook does the work, so make sure it's tucked behind the ear and not sitting on top of it. If buds still work loose during running, the over-ear hook design is the more reliable structure — it's held by your ear, not by friction inside the canal.
how to make apple wired earbuds stay in ear
This is the classic hard case, because those buds have a hard, unsealed shell with no silicone tip to grip the canal. You can't change the tip, so the usual fixes are a foam or silicone cover that adds grip, or routing the cable over the top of your ear so a tug on the wire doesn't pull the bud out. If that still doesn't hold, the honest answer is that the shape is the problem — a hooked design like the kurdene Earbuds is built specifically to stay put where a hard-shell bud won't.
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