Avantree Relay vs Avantree SP850: Which Portable Audio Gadget Fits Your Needs?

The Relay scores higher for usability and setup in the provided data, and reviews frequently call it easy to pair and use. The most common usability caveat is that infrequent users may need to re-check the pairing steps because the device keeps controls minimal.

The SP850 is also commonly described as easy to use, especially for radio scanning and preset saving. Some users note navigation quirks for SD playback and random/shuffle behavior, which can add a learning curve if you manage large music libraries on a card.

The Relay is designed like a compact travel adapter that plugs into a 3.5mm jack and stays out of the way—optimized for airplane use and quick packing. The SP850 is designed as a small handheld/pocket radio with an LED display and onboard controls for tuning and playback. Both are portable, but the SP850 is a more “front-panel interface” product, while the Relay is more of a set-and-forget transmitter once paired.

Both products have mid-range build-quality scores in the provided data (Relay 73; SP850 72) and use plastic housings (Relay lists ABS; SP850 lists plastic). Reviews suggest both are generally well-made for their size and purpose, but neither is positioned as a premium metal-bodied device based on the provided specifications.

Both devices have similar mid-range durability scoring (Relay 74; SP850 69) and plastic enclosures. Reviews suggest they hold up well for typical portable use, but there isn’t enough provided data to make strong claims about drop resistance or long-term wear beyond individual anecdotes.

Both are highly portable, but the SP850 scores slightly higher on portability and has explicit pocket-size dimensions and weight provided (158g). The Relay is also consistently described as compact and easy to carry for flights, with an excellent portability score as well. If you want a pocket radio/speaker you can carry as a standalone device, SP850 stands out; if you want a tiny adapter you plug into a seat screen, the Relay is purpose-built.

Avantree Relay: Feature highlights are its airplane-focused 3.5mm plug-in design, dual-link support for two headphones, and aptX-Adaptive support as listed in the details. It’s a specialized tool for turning a wired audio output into wireless headphone audio.

Avantree SP850: The SP850 is feature-rich in a different way: FM radio, Bluetooth streaming from a phone/tablet/PC, and SD card MP3 playback in one device, with auto-scan and numeric preset saving. It also includes an LED display and a headphone jack.

Choose based on whether you need transmission for headphones (Relay) or a standalone radio/player (SP850).

The SP850 has a non-zero smart-features score in the provided data, but no specific voice assistant or app ecosystem is described in the supplied product details. The Relay does not list smart features. Practically, neither product is presented as a “smart assistant” device; both focus on portable audio playback/connectivity.

The Relay has the stronger setup score and is repeatedly described as easy to pair—one review specifically highlights that turning off phone Bluetooth during pairing can prevent common issues. The main setup drawback is remembering the steps if you only use it occasionally.

The SP850 is also generally straightforward: scan stations, save presets, and pair Bluetooth for streaming. SD-card features (like shuffle/random and navigation) may take a bit more time to learn, based on longer user reviews.

The SP850 is the safer choice if compatibility is your concern: it lists compatible devices including smartphones, tablets, laptops, headphones, and speakers for its different modes.

The Relay is more restrictive by design. It’s described as a Bluetooth transmitter for Bluetooth headphones/earbuds from a wired source, and it explicitly notes it is not for TVs, phones, or hearing aids. If you want a more general-purpose portable audio device, SP850 has broader stated compatibility.

The SP850 includes an LED display (and receives a non-zero display score in the provided data), which is useful for station frequency, modes, and basic playback information. The Relay does not have a display score listed and relies on physical controls and LED indicators (as described in a review mentioning charge LEDs). If you want on-device visual feedback beyond battery/pairing indicators, the SP850 has the clearer display-oriented design.

Audio quality is split by design goals. The Relay is evaluated as a transmitter; reviews often describe sound as clear and stable for movies and general listening, with the added note that latency can vary depending on the connected earbuds/headphones.

The SP850 is a small speaker and is repeatedly praised for being “crystal clear” and strong for its size, but it’s also specified at 2W and positioned for personal listening rather than filling a large room. If you want a tiny speaker to listen without headphones, SP850 is the one built for it; if you want wireless headphone audio from a seat-back screen, Relay is the more relevant choice.

The Relay is fundamentally a connectivity solution: it takes 3.5mm audio input and outputs Bluetooth to headphones/earbuds, including dual connections. Its connectivity score is higher in the provided data, and reviews frequently mention stable pairing.

The SP850 connects to phones/tablets/PCs over Bluetooth for streaming and also offers wired listening via a headphone jack. Connectivity is versatile, but some of the product’s real-world variability comes from FM reception rather than Bluetooth pairing.

The Relay is the stronger battery pick for long sessions: it’s listed for up to 25 hours playtime, and multiple reviews cite very long runtimes on flights (including a report of around 22 hours and another with only partial drain after a long flight). It also has a listed 2-hour charge time.

The SP850 is described as having a rechargeable battery suitable for portable use, with the aggregated review overview mentioning up to 6 hours (and some reviews suggesting a range depending on usage). For long-haul travel listening, the Relay has the clearer advantage based on provided data.

There isn’t enough provided power-consumption detail to quantify efficiency directly. Based on the scores, the Relay rates slightly higher for power efficiency (75 vs 72), aligning with its long stated playtime and travel-oriented battery performance. The SP850’s real-world runtime is often described in the “several hours” range, which is consistent with a small speaker/radio form factor and stated 2W output.

Both products score well on value in the provided data (Relay 86; SP850 85), but “value” depends on whether the device solves your specific problem. The Relay tends to be high value if you regularly encounter seat-back screens with only a 3.5mm jack and want to use your own Bluetooth headphones—especially with its dual-link capability. The SP850 is strong value if you want one small device that can cover FM radio, Bluetooth streaming, and SD music playback with simple controls.

This is effectively a tie: both products are from Avantree and have identical brand-trust scores (78) in the provided data. Customer feedback for both suggests a generally positive experience with the brand, and one SP850 review specifically describes a supportive warranty service interaction.

Customer satisfaction is strong for both based on scores and Amazon metrics. The Relay has 4.3/5 from 6,023 reviews and a slightly higher customer satisfaction score (89). The SP850 has 4.4/5 from 12,090 reviews and a customer satisfaction score of 88, with many reviewers praising sound quality and everyday usefulness. In practice, satisfaction tends to track use-case fit: Relay for flights and wired-to-Bluetooth needs; SP850 for self-contained listening.

The SP850 is the clear leader on warranty/support in the provided scoring data (82 vs 55). Additionally, one detailed review reports a 2-year warranty and describes responsive support and a replacement process. The Relay’s warranty/support score is comparatively low, and there is no explicit warranty detail in the provided Relay product information.