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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-10-03 · 6 min read · Independent comparison
• Monster Open Ear AC336 – biggest strength: A 13mm dynamic driver setup with Qualcomm apt-X HD decoding and a 40mm-class audio spec, plus 21 hours of total playtime and ENC call clarity — a music-first, everyday-comfort open-ear pair.
• Monster Open Ear AC336 – biggest trade-off: IPX6 only. It shrugs off sweat and rain, but it is not built to be submerged, so pool laps are out.
• RR SPORTS IP68 – biggest strength: IP68 sealing rated for submersion up to 2 meters, plus 32GB of onboard storage for roughly 7,000 songs in MP3 mode — genuinely phone-free swimming.
• RR SPORTS IP68 – biggest trade-off: 7 hours of battery and no charging case top-up. Fine for a workout, tight for a long day. Bluetooth is also disabled while swimming.
• Who each is for: Monster for runners, gym-goers, commuters and call-heavy users who want one pair for everything dry. RR SPORTS for swimmers and water-sport athletes who want music in the pool.
The Monster Open Ear AC336 is the more conventional of the two, and that is exactly its appeal. You get a hook-style open-ear design in Deep Black, a plastic charging case, and touch controls you can also manage through an app. The audio side is where Monster leans hard: a dedicated digital audio processor, 13mm drivers, and Qualcomm apt-X HD decoding, with a frequency range of 20Hz to 20,000Hz. In my opinion, that combination points to a pair aimed at people who care about how music sounds, not just whether it plays. The open-ear fit skips the ear-canal seal entirely, which is the whole point — you keep ambient awareness while still getting stereo sound instead of the thin, tinny output a lot of cheap open-ears produce.
Battery and connectivity are the practical story. Bluetooth 6.0, a 33-foot range, auto power-on and pairing when you lift them from the case, and up to 7 hours per charge at moderate volume. The case pushes total playtime to 21 hours, and USB-C fast charging gets you an hour of playback from a 10-minute top-up. That last detail matters more than it sounds: it is the difference between a dead earbud and a usable one on the way out the door. ENC handles your voice on calls, filtering background noise so you are not shouting into a café.
Buy the AC336 if your routine is running, cycling, hiking, lifting, commuting and taking calls — anything sweaty but not submerged. Skip it if you swim laps, want to leave your phone at home entirely, or need guaranteed submersion protection. IPX6 is a real rating, but it is splash-and-sweat resistance, not swim-proofing.
The RR SPORTS IP68 is built around one job: putting music in your ears while you are in the water. The IP68 rating means it tolerates submersion in up to 2 meters, and the sealed construction with a nano-hydrophobic coating is designed to keep sweat, rain and pool water out of the internals. It is also shaped to sit comfortably under a swim cap and around goggles — a detail that tells you who this was designed for.
The second half of the pitch is the 32GB of built-in memory. That is roughly 7,000 songs across MP3, WMA, WAV and FLAC, loaded from your computer over the included magnetic charging cable. Because the player lives inside the headphones, you can swim without a phone anywhere near the water. One thing to internalize before you buy: MP3 mode is the mode for swimming. Bluetooth does not work underwater, which is a physics limitation, not a defect. Above the surface you get Bluetooth 6.0 with a 10-meter range, up to 7 hours of battery, and compatibility with iOS, Android and other devices.
The fit is bone conduction over an ultra-soft silicone frame — lightweight, secure, and deliberately open so you hear ambient sound. That is a safety argument for cycling and running near traffic, and RR SPORTS also frames it as easier on your ears than in-ear or over-ear designs. Note there is no charging case here and no app control. Buy it if you swim, surf, shower or train hard in wet conditions and want phone-free playback. Skip it if you want maximum playtime per charge, app-based touch controls, or a case that recharges on the go.
• Best for swimming and full water immersion → RR SPORTS IP68. IP68 with 2-meter submersion protection versus IPX6 sweat-and-splash resistance. This is not close.
• Best for battery life → Monster Open Ear AC336. 21 hours total with the case and 7 hours per charge, against 7 hours total with no case.
• Best for phone-free workouts → RR SPORTS IP68. 32GB of onboard storage means no phone, no streaming, no signal.
• Best for music quality → Monster Open Ear AC336. 13mm dynamic drivers, apt-X HD decoding and a 20Hz–20kHz range point to a fuller, more detailed sound than a bone conduction driver typically delivers.
• Best for calls → Monster Open Ear AC336. ENC voice clarity is a stated feature; the RR SPORTS sheet lists no call or microphone capability.
• Best for controls and convenience → Monster Open Ear AC336. Touch control plus app support and auto power-on pairing, versus a simpler control scheme with no app.
• Best for safer outdoor awareness → either. Both are open-ear by design, so traffic and surroundings stay audible.
• Best for charging speed → Monster Open Ear AC336. USB-C with a 10-minute charge for an hour of playback; RR SPORTS uses a magnetic charging cable with no quick-charge claim.
If I had to pick one, I would buy the Monster Open Ear AC336 — for most people, most of the time. It covers the widest slice of daily life: better sound hardware, ENC calls, app and touch control, a charging case that triples your runtime, and fast USB-C top-ups. The RR SPORTS IP68 is the better product for exactly one buyer, and for that buyer it is the only real option here: if you swim, IP68 plus 32GB of onboard music beats every other feature on this page. So my rule is simple. Dry training and everyday listening, go Monster. Water, go RR SPORTS.
No. It carries an IPX6 rating, which covers sweat, rain and splashes. It is not designed for submersion, so for pool or open-water swimming you want the IP68-rated RR SPORTS IP68 instead.
Yes — that is its standout feature. It holds 32GB of internal memory, roughly 7,000 songs, and plays MP3, WMA, WAV and FLAC files directly. Just remember to switch to MP3 mode for swimming, since Bluetooth does not transmit underwater.
The Monster Open Ear AC336. It gives up to 7 hours per charge and 21 hours total with the charging case, while the RR SPORTS IP68 offers up to 7 hours and has no case to extend it.
On paper, the Monster Open Ear AC336 — 13mm dynamic drivers, apt-X HD decoding and a 20Hz–20kHz frequency range. The RR SPORTS IP68 uses a bone conduction driver, which trades some audio richness for waterproofing and an open, safety-friendly fit. Prices change often, so check the current price on Amazon before deciding.
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