JBL UA True Wireless Flash X review

The JBL UA Flash X is the company’s latest attempt at taking over the sport wireless earbuds market, which continues to grow at an exponential rate. Highlighted by an indestructible shell, monstrous sound, and stellar battery life (50 total hours), these next-gen fitness buds have the brawn to outmatch category leaders like the Jabra Elite 75t and Beats Powerbeats Pro. 

However, JBL did not learn from the previous version’s mistakes, as specific design elements and a lack of modern features keep the Flash X from achieving greatness.

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JBL UA Flash X: Availability and price

The JBL UA Flash X is currently sold for $169.95 directly from JBL or Under Armour. This model only comes in one color: Black.

JBL UA Flash X: Design

In terms of build quality and look, the Flash X is almost a carbon copy of the original Flash, minus the red trim atop the earbuds. That means you can expect the same minimalist, luxe appearance and insanely sturdy aesthetics. These buds are fully waterproof with an IPX7 rating that allows users to submerge them in up to three feet of water. This certification also ensures protection against rain, sweat, and heavy splashing; feel relief knowing you can wear them in the pool for a post-workout dip.

Whatever materials JBL used to create these buds (it looks mostly like plastic and rubber), there is no denying the exceptional craftsmanship exhibited here. These aren’t buds that will easily break or scuff up when hitting the concrete. They’re pretty light as well, considering how durable they feel.

Details are minimal, with the JBL logo strewn across the side and the raised Under Armour logo on the front acting as a button. The Flash X only comes in Black, but the buds would be a smash if JBL made them part of its Personalization service to create custom colorways and designs. You could also wait to see if a Project Rock Edition is announced, though it may be a while especially since we’re unsure how the current COVID-19 pandemic is affecting JBL’s manufacturing.

I’m under the impression JBL likes to build large, heavy charging cases for the Flash series so that they double as weights when carrying them around. That just doesn’t work for everyone. The slide-out design is cool, and the all-aluminum construction is sleek and water-resistant, a rarity in the category. It’s going to take a two-story fall to even make a dent in it. Still, why does it have to be so cumbersome to carry around?

JBL UA Flash X: Comfort and fit

High-level durability often presents compromises. In the case of the Flash X, it’s bulk and rigidness. These buds stick out and take up all ear real estate, providing very little ventilation. Even with the soft-touch rubberized finish on the inside, they felt harsh on ear skin. The physical buttons also affect comfort since pressing them pushes the buds further into your ears. I sported them for an hour before fatigue started to set in. Simply put, I wouldn’t recommend Flash X for casual listening, only exercising.

On the plus side, the Flash X offers a personalized, secure fit, thanks to the three extra sets of tips and fin sleeves that come bundled. The tips create a tight seal and the fins mold perfectly above the concha to help lock the buds into place. They remained stable during runs, though engaging in more lateral exercises like basketball caused them to fall out on occasion. I did appreciate the great sweat absorption they provided, which prevented slippage when sweating profusely in the summer heat.

JBL UA Flash X: Controls and digital assistant

There isn’t much to report except that the Flash X has responsive controls, be it for music playback or enabling the digital assistant. The button on each bud is multifunctional, so each is programmed with multiple commands that can be executed by the number of press gestures you initiate. For instance, a single press on the right bud will play/pause or answer/end a call, while the right turns on one of two listening modes (TalkThru). There are no volume controls, or on-ear detection to automatically pause music when removing the buds from your ears. Also, the controls are not customizable. Not to mention the listening modes are disabled when using the earbuds in mono mode.

Holding down the right earbud button for two seconds will pull up Siri or Google Assistant, depending on your device. JBL’s mic system picks up vocals accurately, which made executing voice commands a breeze. I also liked how quickly Siri and Google Assistant answered inquiries. Some earbuds have issues with lag and make you wait a few seconds before receiving responses, but not the Flash X. Results were spot-on.

JBL UA Flash X: Audio quality

JBL knows all too well how to engineer a lively sound profile, which is exactly what you get on the Flash X. It’s really no different than what the regular Flash offered, and that’s not bad at all. Bass is bold and rich, while mids and highs are given extra room to breathe, though they can go MIA on certain records.

The heavy bassline at the beginning of A Tribe Called Quest’s “Buggin’ Out” raised the hair on my arms even before the beat dropped. It’s only an 8-second part, but man, it raised my energy levels enough to keep putting up shots on the backyard hoop when nearing the point of exhaustion. The snare cracks were like dropkicks to my eardrum, and the hi-hat action wasn’t too tinny or high pitched, which kept the production well balanced.

It's easy to settle for sports earbuds based on how much boom they deliver, but if you’re spending over $100, you want to seek out a pair that can give you great all-around sound. While the Flash X won’t deliver the same sumptuous audio as the Sennheiser Momentum True Wireless 2, it’s still a noteworthy pair for enjoying non-workout music.

I like to pull up Jazz classics when entering recovery mode, and these buds provided the soothing sonic relief I desired. John Coltrane’s saxophone play on “Blue Train” put my mind and muscles at ease during stretches. It was impressive to hear how well the Flash X reproduced the song’s orchestral elements, creating excellent separation for each instrument throughout the track.

Sports buds aren’t known for having great noise isolation, but the Flash X does a surprisingly good job of keeping environmental noises from entering the soundstage. During my outdoor runs, I barely noticed cars whisking by me, nor did I realize a group of runners was trailing me for about a half a mile. Most importantly, this allowed me to enjoy the music fully, minus any distractions.   

JBL UA Flash X: App and special features

If you’re looking for feature-laden workout earbuds, look elsewhere. All you’ll find on the Flash X is a pair of ambient listening modes. The first is called Bionic Hearing, which basically uses JBL’s TalkThru technology to bring the volume down about 30%, so you can easily interact with others. The second is Ambient Aware, a mode that opens up the soundstage to let sound in, which helps increase awareness of your surroundings. Each one works well, particularly Bionic Hearing, as I was able to communicate clearly with my fiancée on multiple occasions when sharing the same home office space.

The Flash X does not have companion app support. This makes very little sense, especially when lower-priced models like the JBL Live 300TWS are compatible with the JBL Headphones app, providing owners with a handful of extra features that extend functionality. This includes a Find My Buds option, toggle controls, and a built-in EQ that can be customized by selecting different presets (Jazz, Vocal and Bass) or tweaking the frequency levels to create your own sound profiles.

Instead, you’re given a one-year premium membership to UA’s MapMyRun fitness app. It’s a thoughtful gesture and a service that comes in handy for hardcore exercisers who want to monitor their health and performance. Call me spoiled, but I prefer to have personalized sound and control options at my disposal, especially since I already wear an activity tracker (e.g. Fitbit devices, Apple Watch) when exercising.

JBL UA Flash X: Battery life and charging case

JBL managed to double the battery life of the original, increasing it from 5 to 10 hours on a single charge. Realistically, it’s about 9 to 9.5 hours when factoring in the listening modes, high volume and heavy streaming. I used the Flash X daily for 1.5 hours throughout an entire work week and still had about 25% left to work with.

Note: JBL provides scarce details on the Flash X’s quick charging capabilities, only that “Type-C speed charging gets you fully charged earphones just in 2 hours.” Based on my estimation, a 10-minute charge generated 45 minutes of playtime.

The charging case has also received a massive boost in playtime, going from 20 to 50 hours of total battery life. That’s about six extra charges on the go. The lack of wireless charging isn’t a big deal. However, considering the massive amount of power it harnesses, the case could have doubled as a portable charger. I tried using a USB-C-to-USB-C cable to juice up other nearby devices such as my Google Pixel 3XL and Bose 700 headphones: nothing happened. Talk about a missed opportunity.

JBL UA Flash X: Call quality and connectivity

As a calling headset, the Flash X is decent. I wouldn’t use it to take calls in noisy environments because the mics pick up a lot of ambient noise and don’t do the best job of filtering them out. Wind resistance is also an issue; my fiancée noticed some whooshing when taking her call outside in the gazebo. The buds perform much better indoors, producing better clarity for audible results. I used them for several Skype calls and received positive feedback from others.

Setting up the Flash X is a breeze, especially with Google Fast Pair, which automatically detects the buds for instant pairing with recognizable devices. Unfortunately, the Bluetooth range isn’t the strongest. Going from room to room, audio began stuttering at around the 30-foot mark; for comparison, the Live 300TWS granted a solid 40 feet of wireless listening.

Multipoint technology is MIA on the Flash X. It almost seems as if JBL prefers reserving the feature for its on-ear/over-ear headphones, which is a shame if you ask me since there are plenty of current wireless earbuds that support it.

Bottom line

As workout earbuds, which the Flash X clearly are, these are one of the finest-sounding and most well-built offerings in the category. JBL’s soundstage is oomph-tastic, delivering the right amount of punchy bass to fuel your workouts without compromising vocals. Noise isolation is solid as well to keep music sounding full and distraction-free. You’re also getting excellent battery life across the board.

Whether the Flash X’s asking price ($169.95) is justifiable really depends on your needs. Do you want earbuds with everlasting durability, lengthy playtimes, and dynamic audio? Then the answer is clearly yes. If not, know that you can get more functionality and comfort from the Elite Active 75t for a little extra, or splurge on the AirPods Pro should you be one of the many who love sporting Apple’s wireless danglers at the gym.