If you want a compact, travel-focused solution for in ear headphones for meetings on airplanes or shared listening while traveling, choose Avantree Relay; if you need a feature-rich home hub with an optical input and LCD screen for on ear headphones for meetings at your desk or late-night TV sessions, choose 1Mii B3+.
• Avantue Relay: Its biggest strength is portability and dual connectivity for flights using the included 3.5mm adapters, but it lacks an optical input and has no built-in display. This pick is for frequent travelers who need to share audio on planes or in transit.
• 1Mii B3+: Its standout feature is the versatile connectivity suite including Optical (TOSLINK) inputs and a clear LCD status screen, though it is larger and designed as a stationary unit. This pick is for home users setting up a dedicated entertainment center or office station.
The Avantree Relay is engineered specifically for the mobile professional or the avid traveler who refuses to be tethered by wires. Its core design philosophy revolves around solving the specific problem of connecting modern Bluetooth headphones to legacy audio outputs found on older aircraft entertainment systems and gym equipment. The package includes two units, which is a distinct advantage for couples or colleagues who want to sync their own devices simultaneously without fighting over a single transmitter. The inclusion of dual 3.5mm adapters ensures that regardless of whether the airplane seat has a standard headphone jack or a different connector type, the device will function correctly.
For someone looking for in ear headphones for meetings while flying, this device offers a reliable bridge between the plane's audio system and high-quality wireless buds. The Bluetooth 5.3 technology ensures a stable connection even in crowded environments like airports or busy cabins. More importantly, the support for aptX Adaptive and Low Latency codecs means that if you are watching a movie or joining a video call where lip-sync matters, the audio stays perfectly synchronized with the video. There is no noticeable delay that would ruin the immersion of a film or the clarity of a conversation.
Battery life is another critical factor for the traveler, and the Relay delivers up to 20 hours of continuous playback. This duration is more than enough to cover long-haul international flights or multi-leg business trips without needing to recharge. If the battery does drain during a journey, the ability to use the device while it is plugged in via the charging port removes any anxiety about power loss. The controls are straightforward, allowing you to manage volume, pair devices, and check battery levels through simple LED indicators. However, if you require a device that connects directly to a soundbar or a modern TV with an optical port, the Relay will not work out of the box without additional adapters, making it less ideal for a permanent home setup.
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-10-27 · 6 min read · Independent comparison
The 1Mii B3+ is built for the stationary user who wants to upgrade their home entertainment or workspace audio experience without buying new speakers. Its primary appeal lies in its extensive connectivity options, which include both 3.5mm AUX and Optical (TOSLINK) inputs. This flexibility allows it to interface with a much wider range of televisions, gaming consoles, and PCs, many of which have moved away from the traditional 3.5mm jack in favor of digital optical outputs. The presence of an integrated headphone stand and USB-C charging adds a layer of convenience for daily desktop use, keeping the dongle organized and ready when needed.
This device shines when you need to create a quiet zone in a shared living space. The dual-link capability lets you connect two pairs of on ear headphones for meetings or private listening sessions, allowing you and a partner to enjoy a movie or a game without disturbing others. The inclusion of aptX HD support further elevates the audio fidelity, providing richer detail and improved clarity compared to standard Bluetooth transmission. For gamers or cinephiles, the Low Latency mode ensures that the sound matches the action on screen perfectly, eliminating the annoying lag that can break immersion.
A significant differentiator for the 1Mii B3+ is the smart LCD display. Unlike the LED indicators on the Relay, this screen provides real-time data on connection status, active audio modes, and battery levels. You never have to guess what mode the device is in or how much charge remains. The enclosure, made from a mix of ABS plastic and metal, feels sturdy and designed to sit on a shelf or desk. While it supports music playback from USB drives and SD cards, its primary role is as a transmitter. If you are looking for a portable travel companion that fits easily into a small pocket, the B3+ might feel bulky due to its dimensions and lack of a carrying case in the base spec, but for a dedicated home or office station, it is a robust and capable solution.
• Best for air travel and mobility → Avantree Relay: The 2-pack design and included airline adapters make it the only logical choice for flying.
• Best for modern TV and PC setups → 1Mii B3+: The Optical input is essential for connecting to newer televisions that lack a 3.5mm headphone jack.
• Best for visual feedback → 1Mii B3+: The LCD screen gives you instant, readable information about your connection and settings.
• Best for battery independence → Avantree Relay: With up to 20 hours of life and the ability to use while charging, it handles long trips effortlessly.
• Best for audio fidelity on source files → 1Mii B3+: Support for aptX HD and direct USB/SD playback offers higher quality for local media.
• Best for shared listening in transit → Avantree Relay: Two transmitters mean two people can instantly set up their own connections on a flight.
• Best for desktop organization → 1Mii B3+: The integrated headphone stand keeps your gear tidy on a desk or entertainment center.
• Best value for frequent flyers → Avantree Relay: Getting two units in one box solves the "one person needs audio" problem for couples traveling together.
If I had to pick just one device for my personal setup, I would choose the 1Mii B3+ because it offers superior versatility for home and office environments. The ability to connect via Optical cable is a non-negotiable feature for modern TVs, and the LCD display removes all ambiguity about device status. While the Avantree Relay is excellent for travel, the 1Mii B3+ covers more ground for daily use cases like in ear headphones for meetings at a desk or late-night gaming. However, if your primary use case involves frequent flying, the Avantree Relay becomes the clear winner due to its portability and dual-unit value. Ultimately, the 1Mii B3+ is the better all-around transmitter for anyone who spends most of their time at home or in a fixed location.
Yes, both devices support low latency connections suitable for video calls. The 1Mii B3+ offers better integration with PCs via Optical or AUX inputs, while the Avantree Relay works well with computers that have a 3.5mm output.
To take full advantage of the aptX Adaptive and Low Latency features, you should use Bluetooth headphones that also support these codecs. Standard SBC-only headphones will still work but won't match the low delay or high-fidelity claims.
Both allow dual connections, but the 1Mii B3+ is slightly better for home movie nights due to its larger form factor and ability to play directly from USB or SD cards without needing a source device nearby.
No, these are hardware transmitters that operate independently. You do not need to pay for any software subscriptions or monthly fees to unlock the features described in the specifications.
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