How We Research
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want a longer-lasting open-ear bud with adaptive noise cancellation and a case that opens with a slide, choose Monster Open Ear AC510; if you need barely-there clip-on buds that let you hear your surroundings and hop between your phone and laptop, choose Hmusic A24.
• Monster Open Ear AC510 — biggest strength: 25 hours of total playback with the charging case, adaptive noise cancellation and a 13mm dynamic driver tuned for a big, energetic sound.
• Monster Open Ear AC510 — biggest trade-off: It's a traditional open-ear bud that sits over the ear rather than a clip, so the fit and stability depend on the ear-pressure sensing design rather than a clip-on arm — and it lists IPX5 waterproofing in the title but IPX6 in the description, so treat sweat and rain resistance as splash-level rather than swim-proof.
• Hmusic A24 — biggest strength: A ~5.4g open-ring clip-on design with flexible TPU that adjusts to different ear shapes, plus dual-device pairing so you can flip between phone and laptop.
• Hmusic A24 — biggest trade-off: Shorter battery life at 18 hours and a 2-hour charge time, with environmental noise cancellation rather than the adaptive system on the Monster.
• Who each is for: Pick the Monster if playback time and noise handling matter most; pick the Hmusic A24 if all-day comfort, awareness and multi-device switching matter most.
The AC510 is the pick for someone who treats their earbuds as a daily driver and doesn't want to think about charging. Monster rates it at 25 hours total with the case, and that's the single most useful number here — it's the kind of figure that covers a full workday plus a commute plus a workout before you reach for a cable. Charging runs over USB-C, which means one cable for your phone and your buds.
On the audio side, Monster leans on a 13mm broadband PU titanium diaphragm dynamic driver and markets the tuning as "Pure Monster Sound." Read that as a bass-forward, energetic presentation rather than a neutral studio monitor — the kind of sound that flatters pop, hip-hop and gym playlists. The noise story is more interesting than most open-ear buds: it combines traditional active noise reduction with voice recognition and adaptive filtering, so the system is doing more than passively blocking sound. If you take a lot of calls in noisy places, that's a meaningful design choice.
Buy it if you want maximum playback time, a bass-forward sound and smarter noise handling. Skip it if you want the absolute lightest possible bud or you need a clip-style fit that never touches the inside of your ear.
Hmusic A24: Who It's For
The A24 takes the opposite approach: instead of sitting over your ear, it clips on with an open-ring design and weighs roughly 5.4g per bud. That's the headline. At that weight, the design goal is "barely there" — you put them on in the morning and forget you're wearing them. The soft TPU construction flexes and adjusts, so it accommodates a wider range of ear shapes than a fixed-shape bud will.
The other genuinely useful feature is dual-device connection. You can pair the A24 to your phone and your laptop at the same time and switch between them without re-pairing. If you take calls on your computer while your phone sits on the desk, that's a workflow improvement you'll notice every single day. Bluetooth 6.0 handles the connection, with the low latency and stable transmission you'd expect from the current generation.
Battery is the trade-off. Hmusic rates 18 hours of average life with a 2-hour charge time. That's still a full day for most people, but it's noticeably less headroom than the Monster, and the charge time is longer. Noise control is listed as environmental noise cancellation rather than an adaptive system — think "reduces background noise on calls" rather than "actively cancels the world." The open-ring design also means you hear your surroundings, which Hmusic explicitly frames as a safety and awareness feature for outdoor sports.
Buy it if you want the lightest clip-on fit, all-day comfort and seamless phone-to-laptop switching. Skip it if you need the longest possible battery or the more advanced adaptive noise cancellation.
Side-by-Side: Which Should You Choose?
• Best for battery life → Monster Open Ear AC510. 25 hours total versus 18 hours on the A24.
• Best for all-day comfort and light weight → Hmusic A24. ~5.4g per bud with a flexible TPU open-ring clip that adapts to ear shape.
• Best for multi-device workflows → Hmusic A24. Dual-device pairing lets you move between phone and laptop without re-pairing.
• Best for bass-forward, energetic sound → Monster Open Ear AC510. A 13mm PU titanium dynamic driver is the larger, more explicitly "big sound" spec of the two.
• Best for workouts and outdoor awareness → Either, for different reasons. The Monster brings IPX5/IPX6 sweat resistance and a stabilizing fit; the A24 brings an open design that keeps you aware of traffic and surroundings.
• Best for charging convenience → Monster Open Ear AC510. USB-C charging and a slide-open case with a silicone lanyard, versus a 2-hour charge cycle on the A24.
• Best for ear-shape flexibility → Hmusic A24. The flexible clip-on ring is adjustable in a way a fixed open-ear bud is not.
If I were buying one of these tomorrow, I'd take the Monster Open Ear AC510. The 25-hour figure, the adaptive noise cancellation and the 13mm driver cover the three things I actually care about day to day: not charging constantly, hearing calls clearly, and getting sound with some weight behind it. In my opinion, the A24 is the better choice only if lightness and dual-device switching are non-negotiable for you — the ~5.4g clip-on fit is genuinely appealing, and 18 hours is still enough for most days. Check the current price on Amazon before you commit, since that's the one variable that could flip this decision either way. Either way, both are Bluetooth 6.0 open-ear designs with touch controls, so you're choosing between battery-and-noise versus weight-and-flexibility.
Touch control means the earbud's outer panel is a capacitive surface rather than a physical button. You tap it a set number of times to trigger an action — both the AC510 and the A24 use this system, with the A24 specifically using single, double and triple taps to adjust volume, play or pause, answer or end calls, and skip tracks.
Neither the Monster Open Ear AC510 nor the Hmusic A24 lists an on-device way to turn touch controls off — the touch panel is the only control method on both, since neither has a physical button. In practice, the workaround is at the source: disable media controls in your phone's Bluetooth settings for that device, or use your phone or watch to control playback instead.
Because touch controls send standard media commands over Bluetooth — the same signals a headset button sends. A single tap is a play/pause command, a double tap is a track skip, and so on. If your buds are changing songs when you adjust them, it's usually an accidental tap on the touch panel rather than a fault.
No — on the specs, the Monster has the more advanced system. The AC510 lists adaptive noise cancellation combined with voice recognition and adaptive filtering, while the A24 lists environmental noise cancellation. If call clarity in noisy places is your priority, the Monster's design points that way; if you want to stay aware of your surroundings, the A24's open-ring design is built for exactly that.
As an Amazon Associate I earn from qualifying purchases.
We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.
When you buy through links on this page, we may earn a commission from qualifying purchases at no extra cost to you.
Amazon and the Amazon logo are trademarks of Amazon or its affiliates. This site is an independent third-party review and is not affiliated with, endorsed by, or sponsored by Amazon or the product brands mentioned.
See also: ART MyMONITORII Personal Headphone vs JOYO Studio Monitor Headphones, AMORNO Headphones vs LORELEI Q60, CaseSack TAGRY X08 vs Rulefiss Earbuds Sport, Mokata Headphones Kids vs LEEMC Earbuds