JBL Live 400BT Wireless  Headphones Review

The JBL Live 400BT have the same on-ear design as the E45BT. They look slightly more premium, thanks to the more intricate stitching on the headband and polished two-tone finish on the ear cups. However, you would have a tough time telling them apart without the subtle branding of the series lineup on the headband and the slight differences in the control scheme. On the upside, the Live 400BT have a compact on-ear look that some may like. They come in a wide variety of color schemes that are less bright than the E45BT, further adding to their slightly higher-end look and feel.

The Live 400BT, like most JBL on-ears, are not the most comfortable and won't be the ideal option for long listening sessions due to the small cups that constrain the top of your ears. They also have a rather tight fit. On the upside, they're lightweight and breathable, which is nice for casual use.

Like the Live 650BTNC, the control scheme on the 400BT is fairly easy-to-use and delivers decent feedback. The buttons are easy to locate and feel clicky. The Play/Pause multi-function button is indented, as opposed to the raised middle button on the E45BT, which makes it slightly easier to find by touch. You get common functionalities like call/music management and volume control. Also, like many other JBL wireless headsets, you also get a dedicated button for Bluetooth sync, which makes pairing easier. Additionally, you can enable your device’s voice assistant by tapping once on the JBL logo on the left ear cup; however, this can be accidentally triggered when manipulating the headphones, which could be a deal-breaker for some.

You also get a talk-through button that lets you cycle between ambient modes. It doesn't feel as useful, since these aren't noise cancelling headphones and don't isolate you well enough to require a hear-through mode. However, it could come in handy if you want to hear your surroundings without removing your headset.

The JBL 400BT have a decently breathable design. They don't fully cover your ears, so the outer ear will remain relatively cool while you exercise. They still trap a bit of heat and won't be as breathable as in-ears or earbuds, but they should be good enough if you do decide to use them for sports.

The Live 400BT are passably portable on-ear headphones. Like the JBL Live 460NC Wireless, they can fold into a more compact format. They won't be the easiest to carry around on your person, but they can easily fit into a handbag or backpack. Unfortunately, they don't come with case or pouch, which is slightly disappointing.

The JBL 400BT don't come with a case or pouch.

The JBL Live 400BT are decently well-built on-ear headphones. They have the same build and design as the E45BT, but with slightly better metal hinges where they fold. The headband is flexible, has a thin metal frame for reinforcement, and has a slightly better, more premium-looking stitching around the frame. The ear cups are also fairly dense, making the headphones sturdy enough to handle a couple of accidental drops without getting damaged. Unfortunately, like the E45BT, the plastic used in their build feels a bit cheap, especially when compared to the higher-end Live 650BTNC. Overall, they're a decently sturdy headset but don't quite feel as durable as some of the competing options, like the Skullcandy Grind.

The JBL 400BT have a stable and tight fit on the head that should be decently suitable for running. They slipped more often during the testing procedure compared to the over-ear variants in the lineup, but they maintained a stable fit for most casual activities or light jogging. They're also wireless, so there won't be a cable to get in your way during your workouts. However, they won't be ideal if your workouts are particularly intense.

• JBL Live 400BT headphones
• 1/8” TRRS audio cable with an in-line remote
• Micro-USB charging cable
• Manuals

The JBL Live 400BT have a sub-par frequency response consistency. In the bass range, they show more than 18dB of variance at 20Hz, which is significant and quite noticeable. This is mostly due to their on-ear design and sub-par ergonomics, which affects their bass delivery and makes it highly dependent on the position of the headphones. However, their performance is a lot more consistent in the treble range. Consider the JBL Tune 510BT Wireless if you're looking for on-ear headphones that deliver audio more consistently.

The JBL 400BT have great bass performance. Their LFE (low-frequency extension) is at 10Hz, which is excellent. The bass response is relatively flat and even, but consistently over our target curve by about 2-3dB. There's also a 3dB dip in high-bass, resulting in a slight lack of warmth. Overall, the bass on these headphones is deep, thumpy, and punchy enough to handle bass-heavy genres like EDM, hip-hop, and film scores. Unfortunately, their bass delivery varies noticeably across users, and is sensitive to the quality of fit, seal, and whether you wear glasses. The response here represents the average bass response, and your experience may vary.

The mid-range performance of the Live 400BT is great. The response is flat and even throughout the range, which indicates an accurate reproduction of vocals and lead instruments. There's a small under-emphasis in low-mid which will make vocals and lead instruments sound a bit thin, but overall they're well-balanced throughout the mix.

The treble response on the JBL Live 400BT is excellent. The overall response is well-balanced and won't sound too sharp or dull with most lead instruments and vocals. However, treble varies noticeably across users, so your experience may differ.

Imaging for the Live 400BT is great. Their weighted group delay is 0.52, which is within very good limits. The GD graph also shows that the group delay response is almost entirely below the audibility threshold. This ensures a tight and fast bass and a transparent treble. Additionally, the L/R drivers of our test unit were well-matched in frequency, amplitude, and phase response. This helps with the accurate placement and localization of objects (voice, instruments, footsteps) in the stereo image. However, these results are only valid for our unit, and yours may perform differently.

The Live 400BT have a sub-par soundstage. Due to their on-ear design, the drivers don't have enough distance to activate the resonances of the pinna (outer ear) like a loudspeaker, and that shows in the inadequate PRTF accuracy and size values. Also, they don't show a notch in the 10kHz region, further indicating that their soundstage will be perceived to be small and located inside the listener's head as opposed to in front of it.

The noise isolation of the JBL Live 400BT is sub-par. These headphones don't have ANC and their small on-ear cups do not block a lot of low-frequency noise. This means they won't isolate in the bass range much, and will let in the low rumbling sounds of an airplane or bus engine. In the mid-range, important for blocking speech, they isolate by 14dB, which is decent. In the treble range, occupied by sharp sounds like S and Ts, they reduce outside noise by about 38dB, which is decent. If you need a bit more isolation for your commute, then check out the Live 650BTNC or E65BTNC instead.

These headphones have a good leakage performance. The significant portion of their leakage is spread from 400Hz to 4kHz, which is a relatively broad range and will mostly consist of speech, leads, and cymbals. The overall level of the leakage is not very loud, either. With the music at 100dB SPL, the leakage at 1 foot away will average around 32dB SPL and peaks at 44dB SPL, which is under the noise floor of most offices.

The integrated microphone of the Live 400BT, like most Bluetooth headphones, is sub-par. The LFE (low-frequency extension) of 375Hz suggests that speech recorded/transmitted with this mic will sound rather thin. The HFE of 3.4kHz indicates that recorded speech will noticeably lack detail and presence. However, speech would still be decently intelligible with it in quiet environments.

The noise handling performance of the mic is mediocre at best. In our SpNR test, they achieved a speech-to-noise ratio of 13dB, suggesting that the 400BT are best-suited for quiet environments, and may struggle in moderate or loud places.

They have a great battery life that will last you a whole work day without a problem. We measured about 30 hours of continuous playback, although JBL advertises its battery life to be 24 hours. They only take about 1.8 hours to charge fully, which is great. They also turn off automatically after 10 minutes to save some power, which you can toggle on/off in the app. However, if you’re using their microphone and are talking for 10 minutes straight, the headphones will still turn off if no audio is fed through the drivers. They can also be used wired, even when the battery is dead. If you want a pair of on-ear headphones with an even more impressive battery, check out the JBL CLUB 700BT Wireless, though they don't perform quite as well overall.

These headphones are compatible with the JBL Headphones app. It's a pretty decent app that offers control over the talk-through feature and gives you access to a full parametric EQ. You can add as many points as you want and fully customize their sound profile. Unfortunately, it lacks a few features like playback control or room effects. Overall, this app is still a good tool to help enhance your listening experience.

These are Bluetooth-compatible headphones with multi-device pairing. This means they can stay connected to two devices simultaneously, which is very convenient if you have a lot of Bluetooth sources. Unfortunately, they don’t support NFC for quicker and easier pairing, but they do have a dedicated Bluetooth sync button. Unlike the Status Audio BT One Wireless, they don't offer support for the aptX-LL wireless codec.

The Live 400 perform slightly better than most Bluetooth headphones, with 186ms of latency. However, some may still notice a delay when watching video content. On the upside, some devices and apps seem to offer some sort of compensation, so you may not notice it as much.

The JBL Live 400BT come with a standard 1/8” TRRS audio cable that has an in-line microphone as well. This means that they’ll support audio and microphone on pretty much every platform that has the appropriate jack, like gaming console controllers and PCs.

These headphones don't have a base or a dock.