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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-09-17 · 7 min read · Independent comparison
• Linsoul 7Hz — biggest strength: 10mm dynamic driver with a metal composite diaphragm, plus a detachable 0.78mm 2-pin OFC cable you can replace or upgrade.
• Linsoul 7Hz — biggest trade-off: The cable is the upgrade path, but the housing is plastic with a stainless steel faceplate, so it feels less like a single sealed unit than a fixed-cable design.
• keephifi KBEAR Phoenix — biggest strength: Very light in-ear fit with ear hooks, a non-detachable dual aluminium-foil cable, and a Type-C option with a DSP decoding chip.
• keephifi KBEAR Phoenix — biggest trade-off: The cable is not detachable, so if it fails you replace the whole earphone rather than a cable.
• Who each is for: Linsoul 7Hz for listeners who want to tinker, swap cables and use a phone or laptop with no amp; keephifi KBEAR Phoenix for gamers and first-time IEM buyers who want plug-and-play comfort and a Type-C hookup.
The 7Hz Salnotes Zero is built around a single 10mm dynamic driver with a metal composite diaphragm. That diaphragm is the headline spec, and it matters because a metallic composite is designed to resonate and vibrate along with the sound waves more readily than a plain plastic film. The driver is paired with an N52 magnet, and the whole assembly runs at 32 ohm impedance with a stated frequency range of 10 Hz to 20 kHz. In practice, that low-ish impedance and the design intent behind it mean the Zero is meant to be driven straight from a phone, laptop or desktop without a headphone amplifier in the chain.
The housing is a plastic chassis with a stainless steel faceplate, and 7Hz says the ergonomics were measured to balance acoustic performance with comfort and durability. The cable is detachable, using gold-plated 0.78mm 2-pin connectors, and it's made of four cores of high-purity oxygen-free copper in a parallel structure — each core built from 19 strands of 0.08mm wire plus 250D, an arrangement aimed at reducing signal loss and keeping transmission clean. There are three cable variants to pick from: a 3.5mm jack without a mic, a 3.5mm jack with a microphone, or a Type-C jack with a microphone. You also get six pairs of multi-coloured eartips with different collars, so there's real room to fine-tune the seal.
Who should buy it: Anyone who wants a wired IEM they can plug into a phone or computer and just listen, and especially anyone who likes the idea of swapping cables later — the 2-pin connector makes that a genuine option rather than a soldering project. It's also a sensible pick if you use your earphones for more than music: the manufacturer explicitly positions it for movies, games and monitoring, not just albums.
keephifi KBEAR Phoenix: Who It's For
The KBEAR Phoenix is a 10mm dynamic driver IEM too, but the spec sheet tells a different story. It's rated at 16 ohm with 105 dB sensitivity, and its frequency range is stated as 20 Hz to 20 kHz. That low impedance and high sensitivity combination means it should be easy to drive from almost anything with a headphone output — a phone, a handheld console, a laptop. The driver is listed as a DD plus PET type, and the whole earphone weighs 30 grams, which is light for something with ear hooks.
The design is the part KBEAR leans on hardest. It's a polycarbonate shell with a translucent, glossy finish and a phoenix motif, and the company points out it wipes clean with a single pass of a wet cloth. The cable is deliberately non-detachable, and KBEAR makes the case that this is a feature, not a compromise: dual aluminium foil conductors cut signal loss, and removing the plug-and-socket junction removes a common source of noise and a common failure point. The T-shaped plug is shaped to stop the cable twisting and bending at the connector, which is where cheap earphones usually die. The cable itself is described as soft against the skin, and the ear hooks hold the buds snugly in the canal.
You have a choice of 3.5mm or Type-C termination. The Type-C version carries a DSP decoding chip, and KBEAR lists compatibility with Android, iOS, iPadOS, Windows and Linux. Controls are touch-based, and the earphone is aimed at classical, pop, rock, ACG and EDM listeners, plus singers, musicians and drummers.
Who should buy it: Gamers and newcomers to IEMs who want something light that stays put during long sessions, and anyone who wants to plug into a modern phone over Type-C without a dongle. The secure ear-hook fit and low weight are the real selling points here.
Who should skip it: If you already know you'll want to upgrade the cable, or you like swapping between a mic cable and a plain one, the fixed design rules it out. It's also a 16-ohm, 105 dB design, which is very sensitive — if you have a noisy source with audible hiss, that sensitivity can make it more noticeable than a higher-impedance earphone would.
• Best for cable upgrades and tinkering → Linsoul 7Hz. The 0.78mm 2-pin detachable connector and four-core OFC cable make swapping and replacing straightforward.
• Best for a cable you never think about → keephifi KBEAR Phoenix. The non-detachable dual aluminium-foil design removes the plug-socket junction entirely.
• Best for Type-C phone users → keephifi KBEAR Phoenix. Its Type-C option includes a DSP decoding chip and broad OS support.
• Best for listening without an amp on a 3.5mm source → Linsoul 7Hz. At 32 ohm it's specified to run cleanly from a phone, laptop or desktop.
• Best for long gaming or practice sessions → keephifi KBEAR Phoenix. It's light with ear hooks and KBEAR specifically designs the fit to reduce pressure on the ear canal.
• Best for mic and call use → Linsoul 7Hz. You can pick a 3.5mm or Type-C cable with a microphone built in, and switch cables later.
• Best for a distinctive look → keephifi KBEAR Phoenix. The translucent polycarbonate shell with the phoenix motif is a deliberate design statement; the 7Hz goes for a plastic body with a stainless steel faceplate and multiple colour options.
• Best for fit tuning with eartips → Linsoul 7Hz. Six pairs of multi-coloured eartips with different collars are included.
I'd buy the Linsoul 7Hz myself. The detachable 2-pin cable is the deciding factor for me — it means a broken cable isn't the end of the earphone, and it lets me choose a mic cable or a plain one depending on what I'm doing. The 32-ohm, 10mm metal-composite driver design is also clearly aimed at running straight off a phone or laptop, which is exactly how I listen.
If your priority is a light, secure fit for gaming and you'd rather have a Type-C plug with a DSP chip and zero cable maintenance, the KBEAR Phoenix is the smarter pick. In my opinion, that's the one to choose if you want to set it and forget it.
FAQ
No. It's a fixed, non-detachable cable by design. KBEAR argues that removing the plug-and-socket junction reduces noise and extends lifespan, but the practical trade-off is that a damaged cable means replacing the whole earphone.
The KBEAR Phoenix, if you pick the Type-C version — it has a DSP decoding chip and supports Android, iOS, iPadOS, Windows and Linux. The 7Hz offers a Type-C cable with a microphone as one of its three cable options, so it can work too, but you need to choose that variant.
No. The 7Hz is 32 ohm and explicitly designed to be driven by a mobile device without an amp. The KBEAR Phoenix is 16 ohm with 105 dB sensitivity, so it's even easier to drive. Just check the current price on Amazon for whichever variant you pick, since the cable and plug options differ.
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