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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 · 7 min read · Independent comparison
• Otium's biggest strength: IPX7 sealing plus an in-ear design with 11mm dynamic drivers, ear hooks and four ear-cap sizes, so it stays put and sounds full during running, gym work and cycling.
• Otium's biggest trade-off: It's explicitly not built for swimming, and the neckband plus in-ear fit means you always have something sitting in and around your ears.
• GZCRDZ's biggest strength: True IPX8 waterproofing in a 30g bone-conduction frame with 32GB of built-in memory, so you can swim laps without a phone anywhere near the pool.
• GZCRDZ's biggest trade-off: Bone conduction leaves your ear canals open, so it can't give you the same sealed, isolating bass, and the magnetic charging contacts need rinsing and drying after every session.
• Who each pick is for: Otium → runners, gym-goers and cyclists who want sweat-proof, isolating earbuds for dry-land workouts. GZCRDZ → swimmers and open-ear listeners who need music in the water and don't want anything inside their ears.
The Otium set is a sporty neckband pair of in-ear buds, and the spec sheet reads like it was written by someone who actually trains. The headline number is IPX7, achieved with a sealed shell plus nano-coating. Practically, that means sweat pouring down your face during a hard interval session, or getting caught in the rain on a run, isn't the enemy here. The manufacturer is clear that it isn't a swimming headphone, so I'd treat IPX7 as "heavy sweat and weather" protection rather than "take it underwater."
Sound and fit are the other two pillars. There's an 11mm dynamic driver covering a 20Hz–20,000Hz range, tuned for punchy bass and stereo surround, with sound isolation to block out gym noise. The ear-hook design plus four sizes of silicone ear caps is the part I'd actually care about most day to day: a lot of sport buds fail because they work loose, and a hook-plus-multi-size-cap combo is the sensible way to prevent that. Bluetooth 5.1 (listed as 5.3 in the style field — the listing mentions both, and the Bluetooth name shows as "U8" when pairing) gives you a 10-metre range, and you get touch controls for volume, play/pause and track skipping, plus a built-in mic with voice notification of incoming calls.
Buy it if you run, lift, cycle, hike or do yoga and want sealed, isolating earbuds that won't quit on sweat. Skip it if you swim, or if you hate the feeling of anything inside your ear canal. There's a 1-year warranty and the whole thing weighs just 18.14g, so it's genuinely light for a neckband design.
GZCRDZ IPX8: Who It's For
The GZCRDZ X7S is a different animal entirely. It's a bone-conduction headset rated IPX8 — the higher waterproof class — and it's positioned squarely as swimming gear. It weighs 30g and sits on your cheekbones rather than in your ears, transmitting sound through vibration. That's the whole point: nothing plugs your ear canal, so you keep awareness of your surroundings and, crucially, water doesn't get trapped against a driver.
The feature I find most compelling is the dual-mode operation. You can use it as a normal Bluetooth 5.3 headset with a 10-metre-plus range, or flip to MP3 mode using the built-in 32GB of storage. That second mode is what makes it a swim product: you load music, audiobooks or podcasts by dragging and dropping from a Mac or PC, leave your phone in your bag, and the headset plays on its own. It supports MP3 and WMA files. For lap swimming, where Bluetooth simply won't survive the water, this is the difference between usable and useless.
Battery is a 200mAh cell with a claimed 10 hours of music and 10 hours of talk, 300 hours standby, and a 1–2 hour charge (the features say 1 hour, the description says 1–2). Charging is magnetic, which is the standard approach for waterproof gear because it removes an open port. The trade-off is maintenance: the listing is very direct that you should rinse with fresh water and dry the unit after use, keep salt water and seawater away from it for long periods, and clean the magnetic charging contacts so sweat and salt don't corrode them. If you're the type to toss gear in a bag and forget it, this needs a bit more discipline. There's also a note to top up the charge monthly if it sits unused.
Buy it if you swim, or you want open-ear listening for running and cycling where hearing traffic matters. Skip it if you want deep, isolating bass — bone conduction physically can't deliver the sealed thump that an in-ear design like the Otium gives you — or if you'd rather not fuss with post-workout cleaning.
Side-by-Side: Which Should You Choose?
• Best for gym, running and cycling → Otium Headphones. IPX7 sweat protection, ear hooks and sound isolation are made for dry-land training.
• Best for sound isolation and bass → Otium Headphones. Sealed in-ear fit with an 11mm dynamic driver versus open-ear bone conduction.
• Best for situational awareness → GZCRDZ IPX8. Nothing blocks your ear canals, so you hear traffic and surroundings.
• Best for phone-free listening → GZCRDZ IPX8. 32GB of onboard storage plays without any paired device.
• Best for all-day battery confidence → Otium Headphones. The stated 10–15 hour playtime range beats the GZCRDZ's 10 hours, though the Otium figures are inconsistent in the listing.
• Best for minimal maintenance → Otium Headphones. No magnetic contacts to rinse and dry after every session.
• Best for charging speed → GZCRDZ IPX8. A 1–2 hour full charge versus a 15-hour charge time on the Otium.
If I had to pick one, I'd buy the Otium Headphones, because most people searching for IPX7 waterproof headphones are runners, lifters or cyclists, not swimmers — and for that use, sealed in-ear sound, sound isolation and a secure ear-hook fit matter more than open-ear design. The IPX7 rating covers sweat and rain comfortably, and the 10-hour-plus playtime handles a week of workouts between charges. That said, if swimming is your actual goal, don't compromise: go GZCRDZ IPX8, because bone conduction plus 32GB of onboard memory is the only one of the two that genuinely works in the water. In my opinion, the deciding question isn't which is better — it's whether you get wet on land or in a pool.
are headphones waterproof
Not categorically, no — it depends entirely on the IP rating. The Otium Headphones carry IPX7, which the manufacturer describes as protection against sweat and rain but explicitly not suitable for swimming. The GZCRDZ IPX8 goes a step further and is built as a swimming headphone, with the caveat that it shouldn't sit in salt water for long periods and needs rinsing with fresh water afterward.
are headphones water resistant
Many sports headphones are, and both of these qualify. IPX7 on the Otium means a highly sealed shell plus nano-coating that handles heavy sweat and weather, while IPX8 on the GZCRDZ means it can be used in the water itself. Water resistance is not the same as waterproof, so always check the specific rating rather than assuming.
IPX8 is the higher water-protection class of the two, which is why the GZCRDZ is sold as a swimming headset while the Otium is sold as a sweat- and rain-proof sports earbud. In practice, IPX7 covers vigorous sweat and rain; IPX8 covers immersion. If you swim, you want IPX8.
For swimming specifically, yes — bone conduction is what lets the GZCRDZ play without earbuds and without water blocking the driver. The Otium's sealed in-ear design is the opposite approach and is intended for land-based workouts. The GZCRDZ also wins here because its 32GB of built-in memory plays music without Bluetooth, which won't transmit through water.
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