Get insider access
Preferred store
Your browser is not supported or outdated so some features of the site might not be available.
We've recently released our Test Bench 1.6 update for Headphones! Read the Latency R&D Article to learn more.

JBL UA True Wireless Flash Headphones Review

Tested using Methodology v1.4
Reviewed May 24, 2019 at 10:41 am
Latest change: Writing modified Sep 29, 2021 at 12:20 pm
JBL UA True Wireless Flash Picture
7.1
Mixed Usage
6.9
Neutral Sound
7.6
Commute/Travel
8.1
Sports/Fitness
6.9
Office
5.2
Wireless Gaming
5.2
Wired Gaming
6.7
Phone Calls

The JBL UA True Wireless Flash are great sports headphones that stand out thanks to their good audio reproduction and their rugged build quality. They're versatile for a wide variety of music genres, are sweat-proof and waterproof, and their bulky design feels durable for most intense sports. Their fit is good and fairly comfortable, on top of sealing off ambient noise, making them well-rounded for most everyday uses. Unfortunately, they won’t be great for watching videos due to their very high latency, and some may feel like four hours of battery life isn’t enough for a single charge. On the upside, they also offer a 12-month subscription for Under Armour’s fitness app called MapMyRun.

Our Verdict

7.1 Mixed Usage

The JBL Under Armour True Wireless Flash are decent for mixed usage. They have good audio reproduction for in-ears, and their small design is easy to carry around in your commute or at the gym. They also create a good seal in your ears, which isolates a good amount of ambient noise, which is good for public transit or at the office. They're designed as sports headphones thanks to their stability fins and waterproof build. They don’t have the longest battery life for flights or a normal workday, but they’ll be fine for working out. However, their latency is very high, and you shouldn't use them for watching video content and gaming.

Pros
  • Durable and stable fit for sports.
  • Good audio reproduction.
  • Great passive isolation performance.
Cons
  • Very high latency.
  • In-ear fit might not be for everyone.
6.9 Neutral Sound

The JBL Under Armour True Wireless Flash are alright for neutral sound. These in-ears have a good audio reproduction with excellent bass range and mid-range and a good treble. Their bass is slightly thumpy, but some may prefer this. Vocals and leads are accurately reproduced, but they could feel ever-so-slightly nudged to the back of the mix for some. They're very versatile for a wide variety of music genres, but their treble is slightly uneven, which some may not hear. The in-ear fit might not be ideal for long neutral listening sessions as some may feel discomfort after a while.

7.6 Commute/Travel

The JBL Under Armour True Wireless Flash are good for commuting. Their fit blocks out a good amount of ambient noise, including the deep rumble of bus and plane engines. They’ll be a good option for public transit, and since they barely leak, you can mask even more noise by raising your listening volume. Additionally, they're easy to carry around thanks to their portable design, but they don’t have very long battery life on one charge, which won’t be the best option for long rides and flights.

8.1 Sports/Fitness

The JBL Under Armour True Wireless Flash are great for sports. They're designed for working out and will be suitable for most sports. They fit securely inside the ear and don’t move much when being active. Their stability fins will help keep them in place, and since you get different size options, you can find the most stable one for you. They also don’t trap heat inside your ears, meaning you shouldn’t sweat more than usual when wearing these during your workouts.

6.9 Office

The JBL Under Armour True Wireless Flash are decent for the office. They do a great job blocking out work environment noise like ambient chatter and fan noises like A/C systems. They also barely leak, so you shouldn’t bother surrounding colleagues with what you’re listening to. However, their battery life won’t be long enough for you to use them during a full workday; you’ll need to charge during lunchtime. Also, the in-ear fit might not be the best to wear for a few hours, as some may feel discomfort.

5.2 Wireless Gaming

The JBL Under Armour True Wireless Flash are bad for gaming. The microphone won’t be good enough for online gaming, and their latency is too high for video games. The delay between sound and video will be too noticeable and won’t be suitable for this use. They also don’t have good battery life, and overall, will be a very poor choice for gaming.

5.2 Wired Gaming
6.7 Phone Calls
  • 7.1 Mixed Usage
  • 6.9 Neutral Sound
  • 7.6 Commute/Travel
  • 8.1 Sports/Fitness
  • 6.9 Office
  • 5.2 Wireless Gaming
  • 5.2 Wired Gaming
  • 6.7 Phone Calls
  1. Updated Mar 02, 2020: Converted to Test Bench 1.4.
  2. Updated Nov 21, 2019: Converted to Test Bench 1.3.1.
  3. Updated Nov 21, 2019: Converted to Test Bench 1.3.
  4. Updated May 24, 2019: Review published.
  5. Updated May 22, 2019: Our testers have started testing this product.
  6. Updated May 22, 2019: Early access published.
  7. Updated May 20, 2019: The product has arrived in our lab, and our testers will start evaluating it soon.
  8. Updated May 13, 2019: We've purchased the product and are waiting for it to arrive in our lab.

Compared To Other Headphones

Comparison picture

The JBL Under Armour True Wireless Flash are good sports headphones that set themselves apart by their great build quality and audio reproduction. They're also comfortable for in-ears. However, their latency is very high, and some may feel like four hours of battery life isn’t enough.

See our recommendations for the best wireless Bluetooth earbuds for running and working out, the best Bluetooth earbuds, and the best true wireless earbuds.

Jaybird Run XT Truly Wireless

The JBL UA True Wireless Flash and the Jaybird Run XT Truly Wireless are both great sports headphones, but the JBL might have a small edge over the Jaybird for people who want great performance out of the box. They have a better default sound profile, but they don’t have an app with an EQ that can let you customize their sound signature like the Jaybird. On the other hand, you’ll get a battery performance out of the Jaybird, but their control scheme is more limited and harder to use as you need to push the buds inside your ear canal even more, which can be uncomfortable.

Jabra Elite Sport Truly Wireless

The JBL UA True Wireless Flash are better sports headphones than the Jabra Elite Sport Truly Wireless. They are more comfortable and more stable for most sports. They also have a better audio reproduction and are also more versatile for different uses, thanks to their better isolation performance. On the other hand, they don’t have volume controls like the Jabra do, which may be a deal-breaker for some. The Jabra also have a companion app, although the options and controls are limited. Also, our Jabra unit had a noticeable mismatch between the drivers.

Bose SoundSport Free Truly Wireless

The JBL UA True Wireless Flash are better headphones than the Bose SoundSport Free Truly Wireless for most. The JBL are more versatile thanks to their closed-back design that isolates well against ambient noise. They’ll be a better option for commuting, but as sports headphones, it comes to preference. Outside runners might prefer the semi-open design of the Bose to stay aware of their surroundings. The Bose earbud design is also a bit more comfortable, and they have better sound quality and a slightly better battery. On the other hand, you’ll get better range with the JBL, and they have a better microphone for calls. Their case is also more portable and sturdier, on top of being waterproof.

Sony WF-SP700N Truly Wireless

The JBL UA True Wireless Flash are better headphones than the Sony WF-SP700N Truly Wireless. They have better audio reproduction, are more stable for sports, and even if the Sonys are ANC headphones, the JBL have a better isolation performance. The JBL control scheme is easier to use and their build quality feels more high-end, on top of being rated IPX7. They also have about twice the battery life of the Sony. Overall, the JBL are better in almost every aspect, but they don’t support NFC like the Sony do.

Test Results

perceptual testing image
Design
Design
Style
Type In-ear
Enclosure Closed-Back
Wireless Truly Wireless
Transducer Dynamic

The JBL Under Armour True Wireless Flash have a bulky in-ear design that protrudes quite a bit out of the ears. They look like sports earbuds with their stability fins and have Under Armour logos on the back of the buds, which act as buttons. They only come in a single all-black color scheme, with a small red accent.

7.0
Design
Comfort
Weight 0.04 lbs
Clamping Force
0 lbs

The JBL Under Armour True Wireless Flash are decently comfortable truly wireless headphones. They're lightweight, even if they have a bulky design. They fit nicely inside the ears and come with a few options for tip and fin sizes to help you find the most comfortable fit. Some people may not like the in-ear fit and may feel ear fatigue after a while, but these don’t enter the ear canal as deeply as traditional in-ears, thanks to their angled design. If you want a pair of truly wireless in-ears that are even more comfortable, check out the JBL LIVE 300TWS Truly Wireless.

5.6
Design
Controls
OS Compatibility
Not OS specific
Ease Of Use Decent
Feedback Decent
Call/Music Control Yes
Volume Control No
Microphone Control No
Channel Mixing
No
Noise Cancelling Control No
Talk-Through
Adjustable
Additional Controls Voice Assistant

The JBL Under Armour True Wireless Flash have sub-par controls. Each bud has an Under Armour logo that is also a button. On the right ear, you can play/pause your music and skip tracks, but you can’t rewind or go to the previous track. You can also manage calls and mute your microphone. On the left earbud, you can cycle through their ambient and talk-through modes. A single tap will put you in their talk-through mode, which greatly reduces your music level and lets you hear surrounding noise very well. A double-tap will put you in their ambient mode, which will allow you to hear your surroundings, but you can still hear your music fairly loud.

Unfortunately, you can’t jump from one mode to another and need to go back to their normal listening mode before making another input. You can also trigger your device’s voice assistant with a two-second hold on the left earbud. Unfortunately, they don't have any volume controls like other sports truly wireless headphones like the Bose SoundSport Free Truly Wireless.

9.2
Design
Breathability
Avg.Temp.Difference 0.8 °C

Like most in-ears, the JBL UA Flash True Wireless are very breathable headphones, even if their design is quite bulky. They block most airflow inside your ear canal, but their in-ear design will still be breathable and won’t trap too much heat. You shouldn’t feel a big difference in temperature when wearing these during your workouts, and they won’t make you sweat more than usual.

9.2
Design
Portability
L 1.5"
W 1.4"
H 1.3"
Volume 3 in³
Transmitter Required No

Like most truly wireless headphones, the JBL Under Armour True Wireless Flash are very portable. The buds are a bit bulky, but they will still easily fit inside pockets or a bag. They're easy to carry around and come with a nice hard case that is fairly portable, too.

8.0
Design
Case
Type Hard case
L 3.3"
W 1.6"
H 1.2"
Volume 6 in³

These headphones come with a hard charging case that protects the headphones well against physical damage, water exposure, and scratches. The case is a bit bulky but should still fit in most pockets or a bag. It has a high-end feel as it is heavy and made from solid materials. Unfortunately, it has some minor flaws. The tray wiggles around when fully extended, and the earbuds sometimes clip the top of the case when pushed back in. The case is said to be waterproof, and you also get LEDs for battery level indication.

8.0
Design
Build Quality

The JBL Under Armour Flash True Wireless are very well-made, truly wireless headphones. The buds are dense and feel solid enough to survive a few accidental drops without too much damage. They feel like premium headphones, similar to the Sennheiser Momentum True Wireless. Their metal case is also very well-made and feels sturdy. These headphones are certified IPX7 for water resistance.

8.0
Design
Stability

The JBL Under Armour True Wireless Flash are very stable and will be suited for most sports. They're somewhat bulky but still sit nicely inside the ears and don't move much, even when exercising. They have a few size options for tips and fins, which helps you find the perfect fit. You should be able to do most sports with these without them popping out of your ears. Also, their truly wireless design means you won’t have to worry about any cables.

Design
Headshots 1
Design
Headshots 2
Design
Top
Design
In The Box

  • The JBL Under Armour True Wireless Flash headphones
  • Charging case
  • 3x fin sizes
  • 3x tip sizes
  • USB-A to micro-USB charging cable
  • Manuals
  • 12-month subscription code for MapMyRun app

Sound
Sound
Sound Profile
Bass Amount
1.87 dB
Treble Amount
-1.95 dB
9.0
Sound
Frequency Response Consistency
Avg. Std. Deviation
0.21 dB

The frequency response consistency is fantastic. If the user can achieve a proper fit and an air-tight seal using the assortment of tips that come with them, they should get consistent bass and treble delivery every time they use the headphones.

Sound
Raw Frequency Response
9.1
Sound
Bass Accuracy
Std. Err.
1.21 dB
Low-Frequency Extension
10 Hz
Low-Bass
1.31 dB
Mid-Bass
1.74 dB
High-Bass
0.46 dB

The JBL True Wireless Flash's bass performance is outstanding. The LFE (low-frequency extension) is down to 10Hz, which is excellent. Their response is virtually flawless and follows our target curve very well. It has a small overemphasis in the low-bass range, which results in a slight excess of thump and rumble, which fans of bass-heavy music may prefer. Overall, their bass is amazing and has the right amount of punch and body without being overly done.

9.0
Sound
Mid Accuracy
Std. Err.
1.27 dB
Low-Mid
-0.32 dB
Mid-Mid
-1.96 dB
High-Mid
-0.03 dB

Their mid-range is fantastic. The response throughout the range is very well-balanced and flat, which results in an accurate reproduction of vocals and lead instruments.

6.2
Sound
Treble Accuracy
Std. Err.
5.06 dB
Low-Treble
-3.04 dB
Mid-Treble
-4.32 dB
High-Treble
-4.53 dB

The JBL UA True Wireless Flash have mediocre treble accuracy. It's not as bad as the Monster Clarity 101 AirLinks Truly Wireless, but the broad dip throughout the range negatively affects the brightness and detail of vocals and instruments.

8.0
Sound
Peaks/Dips
Peaks
1.14 dB
Dips
1.52 dB
8.9
Sound
Imaging
Weighted Group Delay
0.16
Weighted Amplitude Mismatch
0.98
Weighted Frequency Mismatch
1.26
Weighted Phase Mismatch
2

The stereo imaging is amazing. Their weighted group delay is at 0.16, which is very low. The group delay graph also shows that the entire response is well below the audibility threshold. This ensures a tight bass and a transparent treble reproduction. Also, the L/R drivers of our test unit were well-matched in frequency, amplitude, and phase response. This is important for the accurate placement and localization of objects (voices, instruments, video game effects) in the stereo image. Note that these results are only valid for our unit, and yours may perform differently.

0.5
Sound
Passive Soundstage
PRTF Accuracy (Std. Dev.)
N/A
PRTF Size (Avg.)
N/A
PRTF Distance
N/A
Openness
2.0
Acoustic Space Excitation
0.3

The soundstage is poor. This is because creating an out-of-head and speaker-like soundstage is largely dependent on activating the resonances of the pinna. The design of in-ears and earbuds is in such a way that fully bypasses the pinna and doesn't interact with it. Also, because these headphones have a closed-back enclosure, their soundstage won't be perceived to be as open as that of open-back earbuds like the Apple AirPods (2nd generation) Truly Wireless or the Bose SoundSport Free Truly Wireless.

0
Sound
Virtual Soundstage
Head Modeling
No
Speaker Modeling
No
Room Ambience
No
Head Tracking
No
Virtual Surround
No App
7.5
Sound
Weighted Harmonic Distortion
WHD @ 90
0.359
WHD @ 100
0.150
Sound
Test Settings
Firmware
Unknown
Power
On
Connection
Bluetooth 4.0
Codec
SBC, 16-bit, 48kHz
EQ
No EQ
ANC
No ANC
Tip/Pad
Silicone (small)
Microphone
Integrated
Isolation
8.0
Isolation
Noise Isolation
Isolation Audio
Overall Attenuation
-25.43 dB
Noise Cancelling No
Bass
-10.5 dB
Mid
-20.35 dB
Treble
-46.14 dB

The JBL UA True Wireless Flash have a great noise isolation performance. They only passively block noise as they don’t have an ANC feature. In the bass range, occupied by the rumble of airplane and bus engines, they reduce the noise by about 11dB, which is decent. However, this is rather impressive for in-ears and more than what some active noise cancelling headphones achieve. In the mid-range, important for blocking out speech, they achieved 20dB of isolation, which is very good. In the treble range, occupied by sharp S and T sounds and fan noises like A/C systems, they achieved about 46dB of isolation, which is excellent.

9.7
Isolation
Leakage
Leakage Audio
Overall Leakage @ 1ft
22.68 dB

The leakage performance is outstanding. These in-ears don't leak much, so you don't need to worry about disturbing people around you unless you are blasting your music in a very quiet room. With the music at 100dB SPL, the leakage at one foot away averages at 23dB SPL and peaks at 29dB SPL outside of the bass range, which is noticeably quieter than the noise floor of an average office.

Microphone
Microphone
Microphone Style
Integrated
Yes
In-Line
No
Boom
No
Detachable Boom
No
Mic Yes
6.7
Microphone
Recording Quality
Recorded Speech
LFE
265.23 Hz
FR Std. Dev.
2.81 dB
HFE
3,466.89 Hz
Weighted THD
6.476
Gain
35.93 dB

The recording quality of the microphone is okay. Speech recorded or transmitted with the microphone will sound thin and muffled. This is due to LFE (low-frequency extension) being at 265Hz and the HFE (high-frequency extension) being at 3.5kHz. However, the limited high-frequency extension is a limitation of the Bluetooth protocol and is a problem with all Bluetooth microphones. However, speech will still be decently intelligible with this microphone in quiet environments.

6.3
Microphone
Noise Handling
Speech + Pink Noise
Speech + Subway Noise
SpNR
15.92 dB

The microphone is mediocre at noise handling. In our SpNR test, it achieved a speech-to-noise ratio of 16dB, indicating that it's best suited for quiet environments. But it won't be ideal for moderate and loud environments, as it will have difficulty fully separating speech from ambient noise.

Active Features
5.3
Active Features
Battery
Battery Type
Rechargable
Continuous Battery Life
4.2 hrs
Additional Charges
5.0
Total Battery Life
25.2 hrs
Charge Time
1.5 hrs
Power-Saving Feature
No
Audio While Charging
No
Passive Playback
No
Charging Port micro-USB

The JBL Under Armour True Wireless Flash offer just over four hours of continuous playback with one charge. They take about an hour and a half to fully charge, and you can expect about 20 additional hours of playback from the case, according to the specs sheet. Unfortunately, they don’t have a smart power-saving feature, so be sure to turn the headphones off or put them back in their charging case if you’re not using them.

0
Active Features
App Support
App Name No App
iOS No
Android No
macOS No
Windows No
Equalizer
No
ANC Control
No
Mic Control No
Room Effects
No
Playback Control
No
Button Mapping No
Surround Support
No

These headphones don’t have a dedicated companion app for customization options. However, when buying them, you get a 12-month subscription code to Under Armour’s MapMyRun fitness app.

Connectivity
6.5
Connectivity
Bluetooth
Bluetooth Version
4.2
Multi-Device Pairing
No
NFC Pairing
No
Line Of Sight Range
176 ft
PC Latency (SBC)
386 ms
PC Latency (aptX)
N/A
PC Latency (aptX HD)
N/A
PC Latency (aptX-LL)
N/A
iOS Latency
340 ms
Android Latency
341 ms

The JBL Under Armour True Wireless Flash are Bluetooth compatible but can’t be connected to multiple devices at once. This means you can't switch between your work computer and your phone. They also don’t support NFC for a quicker and easier pairing procedure.

The latency is very high. It's noticeably higher than most Bluetooth headphones, and most people will see an important delay between audio and video. This means you shouldn’t use them for watching videos or gaming.

0
Connectivity
Non-Bluetooth Wireless
Non-BT Line Of Sight Range
N/A
Non-BT Latency
N/A
0
Connectivity
Wired
Analog Audio
No
USB Audio
No
Detachable No
Length N/A
Connection No Wired Option
Analog/USB Audio Latency
N/A

Like expected, you can't use the JBL Under Armour True Wireless Flash headphones wired.

Connectivity
PC / PS4 Compatibility
PC/PS4 Analog
No
PC/PS4 Wired USB
No
PC/PS4 Non-BT Wireless
No
Connectivity
Xbox One Compatibility
Xbox One Analog
No
Xbox One Wired USB
No
Xbox One Non-BT Wireless
No
2.2
Connectivity
Base/Dock
Type
Charging Case
USB Input
No
Line In
No
Line Out
No
Optical Input
No
RCA Input
No
Dock Charging
Yes
Power Supply
USB

These truly wireless headphones come with a hard charging case that has a USB input to power the case but doesn’t have any other inputs. It offers about 20 additional hours of battery life, according to the specs sheet.