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UA Sport Wireless Flex Engineered by JBL review: A sports-centric headphone that lets you run safe at night

The new neckband-style UA Sport Wireless Sport Flex has a built-in LED with three flashing modes for night running -- or walking.

David Carnoy
David Carnoy Executive Editor / Reviews
Executive Editor David Carnoy has been a leading member of CNET's Reviews team since 2000. He covers the gamut of gadgets and is a notable reviewer of mobile accessories and portable audio products, including headphones and speakers. He's also an e-reader and e-publishing expert as well as the author of the novels Knife Music, The Big Exit and Lucidity. All the titles are available as Kindle, iBooks, Nook e-books and audiobooks.
Expertise Mobile accessories and portable audio, including headphones, earbuds and speakers Credentials Maggie Award for Best Regularly Featured Web Column/Consumer
3 min read

Truth be told, I haven't loved previous JBL-engineered Under Armour wireless sports headphones. They didn't fit my ears quite right and they were a little too expensive for what they were. 


UA Sport Wireless Flex Engineered by JBL

The Good

The UA Sport Wireless Flex by JBL is a well-designed neckband-style Bluetooth sports headphone. It's sweat-resistant, fits comfortable and securely and sounds good for the breed. The buds adhere magnetically and there's an LED light strip built into the neckband with three flashing modes for night runs.

The Bad

It's a bit too expensive. Under Armour and JBL should throw in a set of larger eartips to ensure more people can get a tight seal.

The Bottom Line

While it costs more than competitors, the UA Sport Wireless Flex by JBL fits well, sounds good and should please runners and players of other sports, especially if they exercise at night.

The new neckband-style UA Sport Wireless Flex ($130, which converts to about £100 or AU$175) is definitely an improvement. This is a well designed and recommendable headphone for both sports and everyday use.  

Its signature feature is a "RunSafe" LED with three flashing modes, designed to warn motorists when you're running along roads at night. Paired with reflective clothing and common sense, it can provide real peace of mind.

Other sports-centric extras include "bend-and-stay flex zones" in the neckband for an adjustable fit, and a "speed charge battery" that gets you 1 hour of playback with just 5 minutes of charging time. (Battery life is rated at up to 12 hours at moderate volume levels, which is good.) 

It's also worth mentioning that the earbuds adhere to each other magnetically, which allows you to wear them as a sort of pendant and keeps them from flopping around when you don't have them in your ears.

Enlarge Image

What you get in the box.

Sarah Tew/CNET

The real key to any of these in-ear sports headphones is the shape of the earbuds and tips and "fins" that are included. The fins help keep the buds in your ears and the tips should allow you to get a tight seal to maximize sound quality. With earlier Under Armour headphones, the buds themselves were a little bulky (one model had a heart-rate monitor) and not all that comfortable to wear, at least for me. That's not the case here.

I was able to get a decent seal using the largest tips of the two that are provided, but I'd like to see a set of XL tips added to the mix to help ensure more people get a tight seal.

I thought the sound quality -- for a Bluetooth sports headphone -- was quite good. The bass may not have the visceral impact of a more expensive full-size headphones but it's got some kick to it while avoiding sounding bloated or boomy. The midrange sounded pretty warm and natural, and the highs provided ample detail without grating.

The headphone's sound can get a little mashed up when you throw more complicated rock tracks at it, where several instruments are playing at once. That's typical of many Bluetooth headphones, although the best ones let you really hear each instrument distinctly.

For a sports headphone, however, the UA Flex is certainly above average, and I had no issues using it on my commute to and from work on the subway in New York and also on a few runs -- both on the treadmill and outside. Although I encountered a few Bluetooth hiccups, namely moments of interference, the wireless connection was overall solid.

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The LED light has three flashing modes.

Sarah Tew/CNET

The headphones also worked reasonably well as a headset for making calls. The microphone is built into the front of the neckband on the right side. Physical controls include a pause/play button that doubles as the power button, a microphone button that doubles as the mode button for the LED lights and volume controls that double as skip track forward and back buttons when you hold them down.

For those who worry about audio syncing problems when using Bluetooth headphones, I didn't have that issue when watching YouTube videos, and streaming Netflix and iTunes-bought movies. 

I personally like neckband-style headphones, but some people don't. And while UA and JBL haven't done anything all that new or original with this one, it's well designed, fits comfortably and securely, sounds good and has decent battery life.

With so much competition in this price range, I'd like to see it cost less than $100, to better go up against headphones like the upcoming Jabra Elite 45e. But that's my only major gripe with the UA, and hopefully we'll see it discounted in due time. 

UA Sport Wireless Flex

See all photos


UA Sport Wireless Flex Engineered by JBL

Score Breakdown

Design 8Features 8Sound 8Value 7
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