If you want an easy everyday open-ear fit for a big head, choose Monster Open Ear AC336; if you need waterproof headphones with built-in music storage for swimming, choose RR SPORTS IP68. For a shopper comparing over ear headphones for big head comfort, neither uses an over-ear cup design: both use open-ear hooks, so the choice comes down to how you plan to listen.
Monster Open Ear AC336 vs RR SPORTS IP68 at a Glance
• Monster Open Ear AC336 — biggest strength: Up to 21 hours of combined playtime, a charging case, Bluetooth 6.0, and touch controls. Trade-off: Its IPX6 water resistance is not the same as the submersion protection specified for RR SPORTS.
• RR SPORTS IP68 — biggest strength: IP68 protection and 32GB of built-in storage for listening without a phone, including while swimming in MP3 mode. Trade-off: Bluetooth listening is not supported while swimming, and its stated battery life is up to 7 hours.
• Choose Monster if you mainly want open-ear Bluetooth headphones for daily listening, workouts, calls, and a longer overall battery reserve.
• Choose RR SPORTS if swimming, water exposure, or phone-free playback from stored audio is central to your routine.
Monster Open Ear AC336 is a hook-style open-ear Bluetooth model for someone who wants to listen without sealing the ear canal. The product information describes a shape-memory hardshell fit, 13mm drivers, and touch controls. Bluetooth 6.0 is specified, with a range of up to 33 feet. The open design may suit a walk, gym session, or household task when you want audio without the enclosed feel of conventional over-ear headphones.
How We Research
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Battery life is one of its clearest practical advantages. Monster specifies up to 7 hours on a charge at 50–60% volume and up to 21 hours total with the charging case. It also states that a 10-minute charge can provide up to an hour of playback. Those figures make it the more convenient choice of these two if you regularly use headphones through the day and can recharge the case between listening sessions.
The trade-off is its water rating: IPX6 is described as protection against sweat and water, but the sheet does not specify submersion. I’d skip this model if your plan involves swimming or you specifically need headphones rated for underwater use. For anyone searching for bone conduction headphones for big head comfort, note that Monster is an open-ear hook design, not a bone-conduction model. The sheet provides no head-size measurement or adjustability information, so fit for a particularly large head can’t be confirmed from the specifications alone.
RR SPORTS IP68 is the purpose-built option here for swimming and phone-free listening. Its IP68 rating is specified for submersion up to 2 meters, and the product information says the headphones can be worn with a swim cap and goggles. That gives it a clear use case Monster does not claim: taking audio into the water.
Its 32GB of built-in memory lets you load audio files and listen without carrying a phone. The stated supported formats include MP3, WMA, WAV, and FLAC. There is an important mode distinction, though: the instructions say to use MP3 mode while swimming because Bluetooth does not work underwater. Bluetooth 6.0 is for ordinary wireless listening, with a stated range of up to 10 meters; battery life is up to 7 hours.
The design uses soft silicone and bone-conduction audio while leaving the ears open. That makes it a distinct alternative to both sealed earbuds and traditional over-ear headphones, particularly for water-based workouts or outdoor activities. The trade-off is that it is less of a simple Bluetooth-only choice: swimmers need to prepare stored audio, and its stated battery life is shorter than Monster’s total with the case. The sheet also does not give a head-size range, so a big-head fit cannot be guaranteed from the available details.
Side-by-Side: Which Should You Choose?
• Best for swimming → RR SPORTS IP68. Its IP68 rating specifies submersion protection up to 2 meters; Monster’s IPX6 rating does not establish underwater use.
• Best for longer combined battery life → Monster Open Ear AC336. It specifies up to 21 hours with the case, compared with RR SPORTS’ up to 7 hours.
• Best for quick top-ups → Monster Open Ear AC336. The product information says a 10-minute charge can provide up to an hour of playback.
• Best for ordinary Bluetooth use around the house or on a walk → Monster Open Ear AC336. Its stated Bluetooth range is up to 33 feet, compared with RR SPORTS’ 10 meters; both use Bluetooth 6.0.
• Best for a bone-conduction design → RR SPORTS IP68. Monster has an open-ear hook design with dynamic drivers, while RR SPORTS specifies bone-conduction drivers.
• Best for calls according to the listed features → Monster Open Ear AC336. It specifically lists ENC clear-call support; the RR SPORTS sheet does not specify a call-noise feature.
• Best lightweight earphones for big head? Neither can be confirmed from the specs. Both have open-ear hook designs, but neither sheet provides head-size or fit-adjustment measurements. If you’re choosing between them, prioritize the use case—swimming and onboard storage versus everyday Bluetooth and case-supported battery life—rather than assuming one fits a large head better.
I’d choose Monster Open Ear AC336 for everyday listening because its charging case extends stated total playtime to 21 hours, and it offers a clear-call feature alongside Bluetooth use. That is my pick for a big-head shopper who wants an open-ear format, though the specifications don’t confirm fit for any particular head size.
I’d choose RR SPORTS IP68 instead if swimming is part of the plan. Its submersion rating and built-in music storage solve a specific problem that Monster does not.
No. The product information says Bluetooth does not work for swimming. Load audio files and use MP3 mode for underwater listening.
The listed rating is IPX6, with sweat and water resistance described. The sheet does not specify submersion protection, so it is not the swim-focused choice here.
Monster specifies up to 7 hours on one charge and up to 21 hours with its charging case. RR SPORTS specifies up to 7 hours, without a longer combined figure listed.
Neither is an over-ear-cup model; both use open-ear hook-style designs. The available information does not specify head-size fit, so it cannot establish which will be more comfortable for a big head.
• ATUAT AirPods Max Headphones vs Oplp Headphones Insulated Lunch
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.