The JBL 400BT are decent, mixed-usage, on-ear headphones with a well-balanced and customizable sound. They have decent audio reproduction with a slight emphasis on bass, which is great for bass lovers. They also have a good parametric EQ, so you can make them sound the way you prefer; this makes the Live 400BT a bit more versatile than the similarly-designed JBL E45BT. They have an excellent battery life, great wireless range, multi-device pairing, and they're fairly easy to use. Unfortunately, their on-ear design doesn’t isolate much ambient noise and isn’t the most comfortable.
The JBL Live 400BT look almost identical to the JBL E45BT. They have the same portable and breathable on-ear design, but a slightly better control scheme with more functionality. Their build quality also feels a bit more premium, though not as sturdy or durable as the JBL Live 650BTNC. Unfortunately, the on-ear design is much less comfortable than the over-ear designs in JBL's lineup. They also have a talk-through button that allows you to hear your surroundings without removing the headset, but it's a bit less useful than on the noise cancelling models.
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 decently portable on-ear headphones that fold into a more compact format. They won't be the easiest to carry around on your person, but they'll easily fit into a handbag or backpack. Unfortunately, they don't come with case or pouch, which is slightly disappointing.
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.
The JBL Live 400BT are good-sounding on-ear headphones with a closed-back design. They have a deep, consistent, and powerful bass, a decently well-balanced mid-range, and good treble that doesn't sound too sharp or recessed. Their bass may be a bit too thumpy for some, but fans of bass-heavy genres will enjoy their sound profile. However, it can be inconsistent across users. Vocals and lead instruments are fairly balanced throughout the mix, and their treble range is not as recessed as some of the other JBL on-ears that we've tested. Overall, the headphones are better suited for bass-heavy genres, but they would be a decent option for some vocal and instrumental-heavy music too. Furthermore, with their app, you can EQ their sound profile to better match your listening taste and preferences, which is a welcomed addition.
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.
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.
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.
These headphones have a decent harmonic distortion performance. The overall amount of harmonic distortion at 90dB SPL is fairly low, but still above our 'good' value. At 100dB SPL, however, there's a significant change in THD in high-bass and low-treble. This suggests that the JBL may struggle to produce a clean bass under maximum load, and that their treble may sound a bit harsh and fatiguing to some.
The JBL Live 400BT, like most passive on-ears, don't isolate well in loud, noisy environments. Their small cups do prevent some high frequencies from seeping into your audio, but will not block the low rumbling noise of an engine or the chatter of a lively office. This makes them less than ideal for commuting. On the upside, if you can get a good seal on your ears, they don't leak much, so you can mask a bit of ambient noise by turning your volume up without distracting the people around you.
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 21dB, 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 JBL Live 400BT is mediocre at best. In quiet environments, speech recorded or transmitted with it will sound rather thin, noticeably muffled, and lacking in detail. Your voice on the other end of the call should still be relatively easy to understand, but in noisy situations, the mic will struggle to separate your speech from background noise. This means they won't be ideal for environments like a busy street, but should be okay for making a call in a relatively quiet office or room.
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 JBL Live 400BT have an excellent 30-hour battery life, and they're also compatible with the JBL Headphones app that gives you a lot of customization options for their sound. They'll easily last you all day, and even a weekend of moderate-to-heavy use on a single charge. They also have an auto-off timer, which further adds to their overall great battery performance. The JBL Headphones app allows you to add as many points as you want to their EQ and fully customize the sound profile to your liking. This makes the 400BT quite versatile for different listening tastes and preferences. However, the app lacks a few other features that would have been nice to have.
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.
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.
The JBL Live 400BT are Bluetooth headphones that can be simultaneously connected to two devices. This makes them a bit more practical if you often switch between your work computer and your phone. They have an excellent wireless range and you can also use them wired with the provided audio cable that has an in-line microphone. The cable and in-line mic will work with most devices and your console controllers, which is nice. However, their wireless latency might be too high for video content and gaming, but it's slightly lower than most Bluetooth headphones.
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.
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.
The JBL 400BT have an exceptional wireless range. They almost maxed out our testing facility in our line-of-sight range test and had an excellent 60ft of range when the source was obstructed by walls. However, the wireless range is dependent on your device’s signal strength and many other factors, so your results may differ.
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 are decent mixed usage on-ear headphones with an amazing wireless range, battery life, and a good, customizable sound profile. They're not the most comfortable and their build quality feels a bit plasticky, but overall they're decently performing headphones in most aspects, except isolation. See our recommendations for the best headphones, the best on-ear wireless headphones and the best wireless Bluetooth headphones under $100.
The JBL Live 400BT are a little better than the JBL E45BT Wireless. They're both on-ear headphones with a similar sound profile. However, the Live 400BT are a bit better-balanced and have a parametric EQ in their app, making their sound profile more versatile. They have the same build quality and design, but the Live 400BT have a bit more control options thanks to their talk-through mode. They also leak a little less and have longer battery life. On the other hand, the E45BT have slightly lower latency, so you might not notice the delay as much on these. Overall, the Live 400BT would be the better pick for most.
The JBL Live 500BT Wireless are an over-ear variant of the JBL Live 400BT. They look very similar in design, other than their size and larger over-ear cups. The 500BT are a bit sturdier and denser than the 400BT, with a longer battery life and a more consistent frequency response that doesn't vary as much with positioning. However, the 500BT are a bit less neutral-sounding out-of-the-box. The Live 400BT would be a more breathable and compact option for sports, or to carry around on your person. If you prefer over-ears, then the Live 500BT would be the better option; if you want something a bit smaller, then the Live 400BT are a good alternative.
The JBL Live 400BT are slightly better than the JBL Everest 310 Wireless. They're both on-ear headphones with a similar design and sound quality. However, the Live 400BT have a more flexible sound profile, thanks to the parametric EQ included in their companion app. The Live 400BT are also slightly more breathable and have longer battery life. On the other hand, the Everest 310 come with a sturdy carrying case and have a more useful additional feature. Their music sharing button is a bit more practical than the Live 400BT's talk-through mode, since they do not isolate well to begin with. Also, the 310 Wireless have a better microphone performance, a more premium build quality, and easier-to-use buttons, but are not as stable as the Live 400BT, meaning they won't be as good for sports and more demanding activities.
The JBL Live 650 BTNC Wireless are the over-ear noise cancelling variants of the JBL Live 400BT. Being over-ears, the 650 are a bit more comfortable for longer listening sessions; they also isolate a lot better in noise conditions, thanks to their ANC feature, making them a better option for commuting and to use at the office. However, the Live 400BT have much longer battery life and are a lot more breathable and compact for sports and everyday casual use. The 400BT also have a slightly better-balanced sound out-of-the-box, but both headsets can be EQ'd quite heavily thanks to their parametric EQ.