Jaybird X4 Earbuds Review: A Modest, Mostly Good Upgrade
The Jaybird X4 is a modest upgrade with enhanced aesthetics and great sound, but it also has poor battery life and lots of bugs.
Why you can trust Tom's Guide
For the past decade, Jaybird has been regarded as a pioneer of the wireless sports headphones movement. The X series remains a favorite among fitness-conscious consumers and tech critics, with every new model showing significant improvements over the previous release. But the newly released X4 is an exception to that rule.
A marginal step up from its predecessor, the X4 addresses the X3's biggest criticism with the addition of waterproof protection while retaining its greatest strengths, such as an adaptable soundstage, a stable fit and sleek aesthetics. However, buggy performance and disappointing battery life keep the X4 in coach instead of first class.
Design
The X4 is now IPX7 certified, meaning the earphones are sweatproof and waterproof. Now, you can run in the rain and swim with them for 30 minutes in up to a meter of water, according to the company.
The X4 upholds the handsome and ultra-minimalist look of the series with metallic accents coupled with new matte finishes that complement its sleek silhouette. It's much fancier than the brute presence of the Plantronics BackBeat Fit, but I wouldn't go placing it in the sub-luxury category next to the Beats Powerbeats 3. Black, glacier white and jade are the three colors available right now.
Don't be fooled by the lithe, plastic construction of the X4. These things are built to take a beating. The back case of each earpiece and the control module are sturdy, and it would require severe mistreatment to break open either compartment. You'll find much of that same tenacity in the supple, thin wire, which is short but can conveniently be stretched in multiple directions.
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As expected, Jaybird fills up the packaging with a variety of ear tips to accommodate different ear shapes. Other extras include a small carry pouch and a USB charging cable featuring a proprietary connector to snap the earphones on for faster charging.
Comfort and Fit
Compact and lightweight earphones are Jaybird's specialty. The X4 fits the bill, weighing in at a slender 0.5 ounces without the fins or tips. Even with the attachments, they're still lighter than most competitors and rest gently on the neck without any uncomfortable weight.
Stability will never be an issue when sporting these earbuds during workouts or whenever else you're on the move. Both the standard Comply Ultra foam tips and the regular tips lock into the ear canal to form a tight seal, whereas the soft-plastic wings slide easily into the ear to ensure maximum grip. I felt secure knowing that these earbuds would never fall off when I was running outside. Cord management was also on point, with the cinch system keeping the wire from flailing everywhere when I was jumping around.
I felt the earphones pinching my ear after wearing them for 30 minutes.
Unfortunately, with a tight fit comes physical discomfort. I felt the earphones pinching my ear after wearing them for 30 minutes. Swapping out the ear tips didn't make much of a difference, as the buds continued to apply pressure the longer I wore them. In contrast, the Soundcore Spirit Pro showed more compassion for my ears.
Controls and Setup
Jaybird keeps the operation simple on the X4, with a three-button control module located on the right side. Each button is tasked with multiple functions. This involves an intermediate learning curve, but the controls are ridiculously easy to pick up after a few tries.
The central button handles call management, playback and voice assistance. A single tap will answer or cancel a call, or play or pause media. Holding it down for 2 seconds enables Google Assistant or Siri for voice commands. The plus and minus buttons work similarly, controlling volume (single tap) and track navigation (long press), respectively.
I'm a huge advocate of raised buttons because they're much easier to locate and provide better tactility than flat ones. Sadly, that's only half true with the X4. Finding the buttons was never a problem. It's the controls that have issues — they're buggy and suffer from lag. I often had to press them a few times or wait several seconds for a command to execute.
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The pairing process is painless and requires no more than 30 seconds. Holding down the middle button for 5 seconds powers on the headphones and launches pairing mode. Once you see the light indicator blinking red and blue, that's the cue to enable Bluetooth on your device and enter the Pair New Device menu. Find and select Jaybird X4 from the list of available devices, and you're all set.
Audio Performance
Every X model has excelled in sound quality, and Jaybird keeps the momentum going with the X4, promoting a well-balanced soundstage that handles lows and mids properly.
The X4 doesn't skimp on the low end, delivering plenty of boom to boost your adrenaline pre-workout. Tracks like 50 Cent's "In Da Club" illustrate this, channeling full, distortion-free sound to my ear drums. Further testing the X4's low-frequency prowess, I put the earphones through my alternative-rock playlist and enjoyed similar results while listening to much of Green Day's catalog. "Basket Case" and "Longview" were two standouts that demonstrated the X4's emphasis on the low and midrange.
The X4 doesn't skimp on the low end, delivering plenty of boom to boost your adrenaline pre-workout.
As a Rocky IVstan, John Cafferty's "Hearts on Fire" always sparks a second wind during my intense cardio sessions. Everything from the introductory hi-hats to the screeching synthesizers sounded crisp and lively, especially toward the song's energetic and spirited climax. The X4 can handle melodic tunes as well, as shown on Mariah Carey's "Inseparable," with the singer's wide vocal range blending nicely across the infectious piano and thumping bass.
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The X4's soundstage is by no means perfect, but it's superior to that of the Soundcore Spirit Pro. True audiophiles will notice an absence of highs on most songs. The Bose SoundSport Wireless manages to deliver slightly better highs than the X4, but. neither pair of earphones offers an entirely flat-sounding experience. This is where the X4's companion app comes in handy.
Jaybird MySound App
These days, most sports headphones have their own proprietary fitness apps that are basically useless. Jaybird ensures you get your money's worth by offering access to its awesome free MySound app (Android, iOS), which comes loaded with multiple sound profiles and lets users tweak EQ settings to their personal preference. It's the X4's most valuable feature.
The Flat profile is the default preset and what I used to rate overall sound quality. I recommend it if you prefer' near-neutral sound, though it's best to experiment with all the presets, because each is programmed for different music genres. The Bring the Bass preset is perfect for exercising, and it's a better bass-boosting setting than the Soundcore Spirit Pro's Dual-EQ option. Signature is another great profile that aids with post-workout recovery, producing smooth mids and vocal clarity to relax the body.
If nothing suits your sonic palate, there's always the option to modify the EQ on each sound profile or create your own for a more personalized listening experience. Best of all, any changes made to your personal profile are saved and carry over to any new paired device.
Battery Life
During my test run, the X4 gave me an estimated 6 hours of battery life, which is 2 hours shorter than what Jaybird promises. That's sufficient for a handful of workouts, but not enough for an entire week's worth of travel into the city. Playing music at loud volumes drained the battery more quickly — most times, decreasing it by 10 percent within a half-hour of use.
On the plus side, the X4 supports quick-charging technology, so docking it on the charger for 10 to 15 minutes will net you about an hour of listening time. Charging the earphones for an hour should get you up and running at 100 percent.
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Surprisingly, the earphones aren't programmed to automatically shut off when inactive, which kills the battery quickly, especially when they're paired to multiple devices simultaneously. If you want to keep tabs on battery life, you have to rely on your mobile screen or wait for a voice prompt indicating a low battery.
Call Quality and Connectivity
I screened a few calls using the X4, and the results were so-so. My girlfriend and I could hear each other loud and clear on both ends. Raising the volume was never necessary.
However, as good as the built-in mic was for picking up vocals, it's also sensitive to the touch and detected the slightest contact, such as the control module hitting my neck. This produced some disturbance in the process. I also spotted static interference when connected to two devices at the same time.
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Jaybird says the X4 operates within a max range of 33 feet, which is typical for Bluetooth devices. Realistically, it's somewhere between 25 and 30 feet. But even when the earphones were in range, Bluetooth did operate smoothly. Traveling from room to room in my apartment was all good. But leaving my phone in the bedroom to answer the front door presented issues, with the connection dropping out.
Bottom Line
The Jaybird X4 feels more like a partial update than a full-on enhancement of its elder sibling. It's a step up, but not the vast leap we're accustomed to with every new X release. That's not to say the X4 isn't a dependable pair of wireless sports earphones; at $130, they offer enough versatility to warrant their midrange cost.
Sound quality is superb, with the MySound app granting users the luxury of optimizing the soundstage according to their needs, and multiple presets fine-tuned for every music genre. The versatile design, from the tangle-resistant cable to the waterproof exterior, also makes these earphones ideal for fitness lovers. Had it not been for the several bugs or weak battery, the X4 would be thrown into the Editor's Choice discussion.
If you're committed to the Jaybird X series, the X4 is a respectable upgrade.
But you can find better alternatives at higher ($149, Bose SoundSport Wireless) and much lower ($39, Anker Soundcore Spirit Pro) costs.
Credit: Jaybird
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A lifestyle journalist with an affinity for consumer products, Alex has over a decade of experience and has worked with popular publications such as Complex, Thrillist, Men’s Health, Gear Patrol, AskMen, and Hoop Magazine. He currently focuses on audio, reviewing the most coveted headphones in the market for both Tom’s Guide and Laptop Magazine.