We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-09-20 · 7 min read · Independent comparison
If you want a single earpiece for all-day hands-free calling with active noise cancelling on the mic, choose Callez Headset; if you need a tiny travel adapter to stream in-flight audio to two pairs of Bluetooth headphones at once, choose Avantree Relay & SoundJet.
These two products get compared a lot, and honestly they barely overlap. One is a Bluetooth earpiece you wear. The other is a transmitter you plug into an airplane seat. The confusion comes from both being "Bluetooth audio" gadgets with long battery claims, so shoppers searching one often land on the other. Let me separate them properly.
• Callez Headset — biggest strength: CVC8.0 dual-mic noise cancelling with DSP plus Qualcomm aptX HD, paired with Bluetooth 5.0 multipoint so it holds two devices at once.
• Callez Headset — biggest trade-off: It is a call-first earpiece. You get one ear, a boom mic and a plastic build — not a music or movie device.
• Avantree Relay & SoundJet — biggest strength: It turns a 3.5mm AUX jack into a Bluetooth 5.3 transmitter and can feed two headphones at the same time.
• Avantree Relay & SoundJet — biggest trade-off: It only does that one job. Avantree states it is not compatible with phones, car stereos or hearing aids.
• Who Callez is for: Drivers, truckers, office and field workers who live on phone calls.
• Who Avantree is for: Flyers and travelers who want to use their own Bluetooth headphones with seatback entertainment.
The Callez C01 is built around one job: keeping your voice clear on calls while your hands stay free. The spec that matters most is the CVC8.0 dual-mic noise cancelling with DSP. In plain terms, that is an algorithm-and-hardware combo aimed at pulling your voice out of background noise — engine drone, a busy office, airport chatter. Qualcomm aptX HD sits on top of that for the audio path itself, so what you hear on the other end of a call is meant to sound natural rather than thin and robotic.
Connectivity is Bluetooth 5.0 with a stated range of up to 33 feet, and it can hold two devices connected at once. That multipoint detail is easy to skim past, but it is the reason this thing makes sense for someone who carries a phone and a laptop. You can be on a call routed through your computer and still have your phone connected. Controls cover answer and end, mute, volume up and down, and even spoken incoming-number announcements, plus Siri and Google Assistant. Worth flagging: the mute function only works during a call on cell phones, so don't expect it as a general-purpose mute.
Battery is where it earns its place for long shifts. Callez rates it at 8 hours of continuous talk time, 16 hours of music playback and 8 days of standby, with a 1.5-hour charge over Type-C. For a trucker running a full driving day, or someone in a warehouse or on a job site, that talk-time figure is the whole point. Physically it is tiny — 16.74 grams — with an adjustable ear hook, a boom mic that rotates to whatever angle you want, and three sizes of ear tips plus foam covers in the box. It fits either ear. The package also includes a portable carrying case and a Type-C cable, and Callez backs it with 45 days money-back and a 24-month warranty.
Who should buy it: anyone whose day is measured in phone calls — driving, dispatch, sales, remote meetings, customer support. Who should skip it: if you want to watch movies on a plane with your Bose or AirPods, this earpiece cannot do that job at all. It is a monaural headset, not a media device.
The Avantree Relay & SoundJet R1 solves a completely different, very specific problem. Airplane seatback screens still hand you a 3.5mm jack, and most modern headphones are Bluetooth-only. This little adapter plugs into that AUX jack and rebroadcasts the audio over Bluetooth 5.3, so you can use your own headphones instead of the airline's disposable ones.
The headline feature is dual-headphone support. It can connect two Bluetooth headphones at once, which means you and a seatmate can watch the same movie with synced audio. Avantree specifically calls out AirPods and Bose as compatible, along with Bluetooth headphones generally, and it's built on a premium Qualcomm chipset with aptX Adaptive and HD support. That chipset matters for a transmitter, because latency is the enemy here. If audio and video drift apart, a movie becomes unwatchable. aptX Adaptive is the part of the spec aimed squarely at keeping them together.
Avantree rates playback at up to 25 hours, which comfortably covers a long-haul flight plus the return leg, and charging is handled by onboard controls with LED indicators showing connection status so you can see what's paired without digging through menus. Buttons on the device handle pairing and volume. The whole thing is pocket-sized and lightweight — Avantree pitches it as a travel and gym accessory, and the size supports that.
Now the limits, and they matter. Avantree states it is not compatible with phones, car stereos or hearing aids. It is not a general-purpose Bluetooth transmitter for your home stereo or TV. It is a 3.5mm-jack-to-Bluetooth bridge for in-flight entertainment, full stop. If your use case is anything other than "device with an AUX output, headphones with no cable," this is the wrong product.
Who should buy it: frequent flyers, anyone traveling with a partner who wants to share a screen, and people who refuse to fly without their own headphones. Who should skip it: if you need to make and take calls all day, this does nothing for you.
• Best for all-day calling → Callez Headset. 8 hours of talk time and a boom mic are purpose-built for conversation.
• Best for in-flight entertainment → Avantree Relay & SoundJet. It exists to bridge a 3.5mm seat jack to Bluetooth.
• Best for clear voice on calls → Callez Headset. CVC8.0 dual-mic noise cancelling with DSP is the core of its design.
• Best for sharing audio with a companion → Avantree Relay & SoundJet. Dual-headphone support is its standout feature.
• Best for connecting two devices at once → Callez Headset. Bluetooth 5.0 multipoint lets a phone and laptop stay linked together.
• Best if you already own AirPods or Bose headphones → Avantree Relay & SoundJet. It is designed to work with them.
• Best for a full driving shift → Callez Headset. 8 hours of talk time on a 1.5-hour charge fits a workday.
• Best for a carry-on pouch → Avantree Relay & SoundJet. Pocket-sized and lightweight, with 25 hours of playback.
Notice there is no real head-to-head here. You would not swap one for the other — they occupy different pockets of your life. The only reason to compare them is that both promise long battery life and Bluetooth audio, and that is where the similarity ends.
In my opinion, most people searching these two names should buy the Callez Headset. The reason is simple: the C01 does something you need almost every day — take and make calls with clear audio — and it does it with real noise-cancelling hardware, multipoint pairing and a warranty. The Avantree Relay & SoundJet is excellent at what it does, but what it does is a few flights a year for most buyers.
That said, if you fly often and own good Bluetooth headphones, the Avantree is the one thing that makes seatback entertainment bearable. Buy both if your budget allows. If you must pick one, pick based on whether you talk more than you fly.
FAQ
That is exactly what it is designed for. It uses CVC8.0 dual-mic noise cancelling with DSP to isolate your voice, and it supports mute, volume control and voice assistants. It is a call-focused earpiece first.
No. Avantree states it is not compatible with phones, car stereos or hearing aids. It is intended for 3.5mm AUX sources like airplane seatback systems, paired to Bluetooth headphones such as AirPods or Bose.
They are rated differently, so compare the right numbers. Callez claims 8 hours of talk time and 16 hours of music playback. Avantree claims up to 25 hours of continuous playback. If you are talking, Callez's talk-time figure is the relevant one; if you are streaming a movie, Avantree's 25 hours wins.
Yes — I do not quote prices here because they change. Use the "Check latest price on Amazon" button on this page to see the current cost of whichever model fits your needs, then decide.
As an Amazon Associate I earn from qualifying purchases.
We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.
When you buy through links on this page, we may earn a commission from qualifying purchases at no extra cost to you.
Amazon and the Amazon logo are trademarks of Amazon or its affiliates. This site is an independent third-party review and is not affiliated with, endorsed by, or sponsored by Amazon or the product brands mentioned.