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If you want open-back planar sound for critical listening at a desk, choose SENDYAUDIO Apollo Open-Back Planar; if you need all-day wireless freedom with adaptive noise cancelling, choose Technics Reference Class Hi-Fi. And to get the toddler question out of the way up front: neither of these is a kids' product — I say that plainly because plenty of shoppers land here searching for the best clip on earbuds for toddlers, a headset for toddlers, or wireless open ear headphones for toddlers, and that is a different category entirely. Everything below is about two adult-oriented designs that sit at opposite ends of the headphone spectrum.
• SENDYAUDIO Apollo's biggest strength: a 68mm planar magnetic driver in a wood, open-back over-ear design, with a 20Hz–40kHz range, 16 ohm impedance, and a braided 6N OCC cable with 2.5mm dual connectors.
• SENDYAUDIO Apollo's biggest trade-off: it's wired only, has no noise control at all, and the open-back build means it leaks sound both ways — it's a quiet-room headphone, not a commuter one.
• Technics Reference Class Hi-Fi's biggest strength: true wireless Bluetooth 5.3 earbuds with adaptive noise cancelling, Dolby Atmos with head tracking, multipoint across three devices, and up to 10 hours per charge (28 with the case).
• Technics Reference Class Hi-Fi's biggest trade-off: it's in-ear with a sealed fit, so you get isolation instead of an open, airy stage, and it depends on battery and a charging case to work at all.
• Pick the SENDYAUDIO Apollo if you listen at a desk or in a dedicated quiet spot and want an open, spacious over-ear presentation.
• Pick the Technics Reference Class Hi-Fi if you move between phone, laptop and tablet all day and want one pair of earbuds that keeps up.
The Apollo is built around one idea: a big planar magnetic driver in a wooden, open-back over-ear shell. That 68mm diaphragm is large for a headphone driver, and the design notes describe a magnetic circuit and magnetic distance tuned over years of experimentation to balance resonance, plus a high-damping composite diaphragm meant to keep vocals natural and bass solid. The spec sheet backs the ambition: a 20Hz–40kHz frequency range and 16 ohm impedance, which is low enough that it doesn't demand a monster amplifier to reach reasonable volume. The "Apollo" name comes from the way the black and nickel steel mesh layers catch light — a design flourish, but a real one.
Buy it if you want an open, transparent presentation for music at a desk, you're fine with a cable, and you already own a decent source. Skip it if you need to take calls on the move, ride transit, or listen in a shared room where leakage would bother people. In my opinion, this is a sit-down-and-listen headphone, not a lifestyle one. If you're comparing costs, check the current price on Amazon rather than trusting any number you see floating around.
Technics Reference Class Hi-Fi: Who It's For
The Technics Reference Class Hi-Fi is the opposite philosophy: a fully wireless in-ear system that tries to adapt to wherever you are. The headline features are adaptive noise cancelling that responds to your environment, Dolby Atmos with head tracking so spatial audio shifts as you turn your head, and a Voice Focus AI chip aimed at keeping calls clear. It uses magnetic fluid drivers — Technics claims low distortion, accurate bass and smoother mid-highs — and covers a 20Hz–40kHz range, matching the Apollo on paper at the extremes even though the two produce sound in completely different ways.
Practicality is where it pulls ahead for most people. Bluetooth 5.3, multipoint across three devices so you can prioritize between a laptop and a phone, touch controls, and a charging case that takes the total to 28 hours (10 hours per charge with noise cancelling on). The earbuds are described as 10% smaller and 16% lighter than the earlier EAH-AZ80, with a lower-profile shape — a real difference if you've found in-ears uncomfortable before. They're also wireless-charging capable, which is convenient but one more thing to keep topped up.
Buy them if you want one pair that handles commuting, calls, travel and video without cables. Skip them if you dislike in-ear fit, don't want to manage battery, or specifically want an open-back over-ear experience — the sealed design gives you isolation, not airiness. And again: these are adult earbuds. Nothing about them suits a toddler, so if a small child is the actual listener, this is not the product.
Side-by-Side: Which Should You Choose?
• Best for commuting and travel → Technics Reference Class Hi-Fi. Adaptive noise cancelling plus a sealed in-ear fit is the only one of the two that works on a plane or train.
• Best for calls and meetings → Technics Reference Class Hi-Fi. The Voice Focus AI chip and three-device multipoint are aimed squarely at this.
• Best for long desk sessions → SENDYAUDIO Apollo Open-Back Planar. No battery to run down, and the light headband is designed to avoid fatigue.
• Best for movie and spatial-audio fans → Technics Reference Class Hi-Fi. Dolby Atmos with head tracking is unique to it here.
• Best for people who hate cables → Technics Reference Class Hi-Fi. The Apollo is wired only, with dual 2.5mm connectors.
• Best for quiet-room sound quality potential → SENDYAUDIO Apollo Open-Back Planar. The planar driver and OCC cable are the audiophile-oriented build.
• Best for parents shopping for a child → neither. Neither product is designed for toddlers; look at dedicated kids' audio gear instead.
If I had to choose one, I'd buy the Technics Reference Class Hi-Fi. It fits more of real life — wireless, noise cancelling, multipoint, 10 hours per charge — and I'd get more use out of it across a normal week. The SENDYAUDIO Apollo is the better pick if you have a quiet desk, a wired setup and a taste for open-back planar sound, and in that specific context I'd recommend it without hesitation. Just be clear about the toddler angle: neither is a headset for toddlers or a set of wireless open ear headphones for toddlers, and no amount of spec-sheet cleverness changes that.
Not really. It's wired, has no noise control, and the open-back design leaks sound in both directions. It's happiest at a desk in a quiet room.
Yes. They use Bluetooth 5.3 with three-device multipoint and a Voice Focus AI chip for call clarity, so switching between a phone and laptop is straightforward.
The Technics, by default — up to 10 hours per charge and 28 hours with the case. The SENDYAUDIO Apollo has no battery at all because it's a wired headphone.
No. Both are adult products — one is an open-back over-ear wired headphone, the other is a set of in-ear wireless earbuds. For a small child you want purpose-built kids' audio gear, not either of these.
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