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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-09-24 · 7 min read · Independent comparison
• COOMAX Mini Spy Earpiece — biggest strength: an earpiece measuring roughly 3x2 mm that sits deep in the ear canal and stays essentially invisible, receiving audio wirelessly over RF from a neck loop.
• COOMAX Mini Spy Earpiece — biggest trade-off: it needs a 3.5 mm jack or a separately sold adapter, the loop transmitter runs on two 9V batteries, and there is no noise control at all.
• LUDOS Zenith USB C — biggest strength: a straightforward wired USB-C connection with a full-range 20Hz–20,000Hz dynamic driver, plus a 5-year warranty.
• LUDOS Zenith USB C — biggest trade-off: it is wired only, so there is no wireless freedom, and the USB-C plug will not fit older 3.5 mm-only gear without a dongle.
• Who each pick is for: the COOMAX is for someone who needs covert, unnoticeable audio; the LUDOS Zenith is for anyone who wants reliable everyday earbuds for USB-C devices.
The COOMAX Mini Spy Earpiece is a genuinely unusual piece of kit. The earpiece itself is tiny — about 3x2 mm — and it has no battery inside it. Instead, it picks up sound inductively from a skin-colored loop you wear around your neck or under your clothes, which is connected by a 3.5 mm plug to your phone. The loop does the transmitting and takes two 9V batteries; the earpiece just sits in your ear canal and receives. That is the whole trick, and it is why the thing can be so small.
What it does best is disappear. You clean and dry your ear, let the earpiece fall into the canal, then slowly raise the volume until you hear it. To get it out, you use the included magnet. Wearing one is usually enough for clear sound, though the instructions note that two earpieces can improve things. It works with any mobile phone that has a 3.5 mm jack, or with an adapter you supply yourself. There is a microphone on the wire, so you can talk hands-free, and media controls are push-button.
Who should buy it? Someone who specifically needs audio that nobody else can see or hear — a discreet comms setup, a hidden cue feed, or a private channel in a situation where a normal earbud would be obvious. If invisibility is the entire point, nothing else in this comparison comes close.
Who should skip it? Almost everyone else. There is no noise control, the frequency range is narrow at 85Hz–255Hz, the loop needs fresh 9V batteries, and the whole procedure of seating and removing the earpiece takes care. If you just want to listen to music on your commute, this is the wrong tool.
The LUDOS Zenith USB C is the opposite philosophy: a normal, wired, plug-and-play set of in-ear earbuds built for the connector that modern phones actually use. It terminates in a USB Type C plug, which is what current iPhone, iPad, Samsung Galaxy and similar USB-C devices take. No adapter, no batteries, no ritual — you plug it in and it works. It comes in Pink, with a thermoplastic elastomer build and a 5-year warranty.
On paper the audio side is conventional but sensible: a 32-ohm dynamic driver covering 20Hz to 20,000Hz. That is a full-range spec, which is exactly what you want for music, podcasts, calls and video. The control scheme is touch-based with a button controller, and it includes call control. It also offers sound isolation, which means the seal passively blocks some outside noise — useful on a bus or in a shared office, and something the COOMAX simply does not have.
Who should buy it? Anyone whose daily driver is a USB-C phone, tablet or laptop and who wants one pair of earbuds that lives in a bag and never needs charging. The 5-year warranty is a meaningful signal that the maker expects it to last, and the teen-to-adult sizing note means it is pitched at a broad range of users, including kids with a USB-C device. The touch controls make answering calls easy without pulling out the phone.
Who should skip it? People with older 3.5 mm-only hardware, and anyone who wants wireless freedom — this is a wired product end to end. If you need to move around a room untethered, look elsewhere. And if you want an earpiece nobody can spot, the Zenith's in-ear shape is visible like any normal earbud.
• Best for invisibility → COOMAX Mini Spy Earpiece. A 3x2 mm earpiece in the ear canal is about as hidden as audio gets.
• Best for everyday listening on modern phones → LUDOS Zenith USB C. USB-C plugs straight into current iPhone, iPad and Galaxy devices.
• Best for older or audio-jack devices → COOMAX Mini Spy Earpiece. It runs on a 3.5 mm jack, though an adapter is not included.
• Best for sound quality on paper → LUDOS Zenith USB C. 20Hz–20,000Hz full range versus the COOMAX's narrow 85Hz–255Hz band.
• Best for blocking outside noise → LUDOS Zenith USB C. It lists sound isolation; the COOMAX lists no noise control at all.
• Best for low-maintenance ownership → LUDOS Zenith USB C. No batteries to swap and a 5-year warranty.
• Best for covert, hands-free comms → COOMAX Mini Spy Earpiece. RF reception plus a wire microphone is built for that job.
• Best for kids and teens → LUDOS Zenith USB C. The age range explicitly covers kids, teens and adults.
For the vast majority of people reading this, I would buy the LUDOS Zenith USB C. It is the honest, low-friction choice: USB-C for the devices you actually own, a full-range driver, sound isolation, touch and button controls, and a 5-year warranty that backs the purchase. In my opinion it is the better everyday earbud by a wide margin. The COOMAX Mini Spy Earpiece is the pick only if concealment is non-negotiable and you accept the battery-powered loop, the narrow frequency range and the fiddly seating. Buy for the job you actually have — most of us have the Zenith's job.
how to disconnect headphones from all devices
Disconnecting varies by product. The LUDOS Zenith USB C is wired, so you simply unplug the USB-C connector from the device and it is disconnected. The COOMAX Mini Spy Earpiece is also cable-based at the phone end — unplug the 3.5 mm plug from the handset. Neither relies on a paired-device list you need to clear.
how to make headphones forget all devices
Wired headphones like these two do not store paired devices, so there is nothing to forget. The Zenith connects physically through USB-C, and the COOMAX connects physically through its 3.5 mm plug into the loop transmitter. Removing the plug ends the connection entirely. If you are dealing with a Bluetooth model, the process lives in that device's own settings.
how to unpair headphones from all devices
Again, unpairing only applies to wireless Bluetooth gear. The LUDOS Zenith USB C and the COOMAX Mini Spy Earpiece are not Bluetooth headphones in the pairing sense — the COOMAX uses RF reception from a loop that plugs into your phone. Unplug, and you are done. For a true Bluetooth earbud, you would remove it from each device's Bluetooth menu.
how to listen to two devices at once with headphones
You cannot do this with a single wired connection. The LUDOS Zenith USB C has one USB-C plug for one device, and the COOMAX Mini Spy Earpiece has one 3.5 mm plug feeding its loop transmitter. To hear two sources at once you would need a mixer or splitter feeding a single input, which is outside what either product is designed to do on its own.
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