Sony WI-XB400 Review

The Sony WI-XB400 EXTRA BASS wireless in-ear headphones are inexpensive earbuds for everyday use. Although they are marketed to fans of the bass-heavy genre, their overall sound profile remains relatively balanced without any signs of boominess. They offer a fairly consistent fit, won’t fall out during exercise, and have a long battery life that lasts all day. Unfortunately, they are not compatible with the Sony Headphones Connect app for customization, and their sound isolation is rather disappointing. Nonetheless, they’re a good choice for those looking for basic wireless headphones with extra bass.

Bass: Lower than expected bass
The bass isn’t neutral, but it’s far from bass either. Compared to the more natural-sounding Sony WF-1000XM4, they have a bass response of only a few dB.

This is very unusual for “Extra Bass” headphones, as their bass usually sounds bloated.

In contrast, the Sony WI-XB400 outputs relatively impressive bass accuracy (for the price), with good extension and just the right amount of rumble.

The bass bottom drum is very precise, preventing drum solos from being drowned out by the mix. I had no problem listening to a variety of music genres.

Midrange: Sony’s Unusual Tuning
This is where things get confusing. The transition from high bass to midrange produces a more neutral sound, which prevents the bass from confusing the midrange.

However, Sony decided to lower the midrange to about 2kHz and then bring it back to about 4.5kHz. This creates a strange imbalance that makes the sound feel soft and quadratic, as if most of the music is lost.

The instruments suffer the most, lacking detail and presence in the mix. The vocals also lack texture and sound a bit dry.

Treble: Lacking some air and clarity
Higher frequencies are also muted. While cymbal crashes have good presence and good texture, they lack air.

The upper midrange between 5-10kHz drops too deeply, taking away clarity. As a result, the highs sound dull.

Comfortable fit

While the comfort level is good, the neckband design of the earbuds can compromise overall stability. You can use them for walking, but not for running.

The Sony WI-XB400 apparently only comes in 3 sets of earbuds, small, medium and large. The interesting thing is that they provide the same tight seal no matter which earbud size you use.

The wireless headphones themselves are comfortable to wear and don’t create any hot spots. All earbud sizes provide good stability when walking around.

However, once you start running or shaking your head, the earbuds will stick out of your ears. This can happen quickly, but luckily the cable catches the flying earbuds. There are no fins or hooks to ensure a more stable fit.

In addition, the module sometimes slips over your shoulder or tucks under your shirt, pulling out the buds when you try to turn your head.

As a result, the Sony WI-XB400 are not designed for sports activities. They are only suitable for easy walks and home use.


While the overall build quality is similar to other wireless earbuds under $50 that don’t have an official IP rating, there is one flaw that makes them more susceptible to water damage, which lowers their score.

The overall aesthetics and construction are nearly identical to the Beats Flex. Both have flat cables to prevent tangling, use 2 modules per side, and use magnets to connect the two earbuds.

Sony WI-XB400 Charging Port
The flap on the charging port is not practical. I’ve seen many torn flaps and this one will eventually tear.
In addition, they lack an official IPX rating, which means that even excessive sweat can damage them.

However, almost all earbuds use some sort of metal or fabric mesh in the nozzle to protect the internal components from debris, earwax, and sweat.

Microphone Quality

Even in a quiet room, your voice can suddenly burst and distort. The aggressive background noise cancellation feature even removes tiny words and splices them together so it looks like you’re speaking faster than usual.

Thank goodness you’re understandable, so the person on the other side should know what you’re talking about.

On the other hand, speaking in a noisy environment can further distort your voice. It’s almost impossible to understand.

In conclusion, although the Sony WI-XB400 can make emergency calls, please try to avoid making regular calls.

Noise Isolation

Sony earbuds are only good in terms of passive noise isolation. They will pass a lot of ambient noise, but as long as you play music you’ll be fine.

The earbuds on the Sony WI-XB400 create a good seal between you and outside noise. It’s not great, but it will provide good isolation when you’re listening to music during your daily commute.

Sony WI-XB400 Ventilation Ports
There are two large vents on the back of the earbuds.
The housing has 2 vents to prevent the sound from becoming bloated. It also helps tighten up the bass.

However, these vents are larger than usual, which is probably why they pass more noise than other earbuds, despite being well sealed. This means that you can find earplugs with better noise isolation elsewhere.


The Sony WI-XB400 offers decent Bluetooth functionality with a stable Bluetooth connection and range, multi-point support, and no video latency.

The wireless earbuds use Bluetooth 5.0 to establish a stable, lag-free connection. During normal use, with a smartphone in my pocket, I did not experience any random dropouts.

Bluetooth range is also good, though slightly better than average. The earbuds can withstand a distance of about 50 feet with 2 brick walls in between.

We will be happy to hear your thoughts

Leave a reply