To test the B400, I used the earphones for almost a month while listening to music, watching videos and even when answering phone calls on the go.
Build quality and comfort
Starting out with build quality, I have to say it is a definite plus for the B400 that it not only uses detachable cables, but you get two in the box – I find if an earphone is going to fail, it is usually down to the cable before anything else. The pre-attached cable also feels high quality, with metal plating around the 3.5mm jack area and at the bifurcation where the left and right earphone cables split.
On top of that, even if you somehow get through both of the included cables, the MMCX connector is widely used and it is very easy to find a replacement online. So generally, I have to say Brainwavz is doing very well in this regard.
The B400's driver housing is made from plastic as we mentioned, and certainly I think it looks lovely from a purely aesthetic stand point. I do just wonder about that material decision from a practical perspective though – they've held up perfectly during my testing, but I would not at all be surprised if the housing were to crack or split if the earphones were dropped onto a hard surface.
In fairness, as I said I've not had any issues like that during my testing, and I am usually quite rough with my earphones and just shove them in a pocket or backpack. There is obviously a hard carry-case included as well which only helps, but I do have to say I have less concern about breaking the 1MORE Quad Driver with its metal housings than I do for the B400.
Now, in terms of comfort, I haven't really had any issues in this regard. Obviously as we already mentioned these are IEM style earphones which you wear over the ear via the integrated ear hooks in the cable. This is not a problem for me at all and I found the overall shape of the earphones would fit in around my ear without any discomfort. Occasionally the ear hooks would snag on my glasses when taking the earphones out, but that won't be an issue for everyone and is fairly minor in the first place.
My main gripe in terms of comfort is that the cable is prone to spinning around at the MMCX connector on each earphone. That's because the cables don't lock in place – you just insert them, and they will definitely stay connected, but the cable just spins around the connector. It doesn't sound like a big deal and it isn't uncommon with other earphones, but it is annoying when you have the ear hook in the perfect position, and then it spins out of place. A small lock to just stop the spinning would help a lot here.
The last thing to talk about is the choice of ear tips. By default, a medium size silicon pair are attached to the earphones, and while I found these fit my ears quite well, I usually find silicon tips can slip out once they warm up in my ear. It's good then that a pair of Comply T-100 foam tips come included and I found these as good as you'd expect for Comply – great isolation, nice and comfy and also just the right size for me. I don't think it would've hurt to include more foam tips, but a 3-pack of Comply tips is only an extra £15.
Sound
Moving onto what we are all here for, though, and that is sound quality. Overall I would describe the B400 as a slightly v-shaped earphone, with enough bass presence to just about give it an overall warm tilt, but it is far from a bass-heavy IEM.
Starting with the bass then, like I said there is a slight emphasis on the low-end with the B400 which creates a slightly warm presentation. I am trying to be careful with my words here as the B400 is certainly not bass heavy – compared to the 1MORE Quad Driver, which has a much more prominent bump to the mid-bass, it sounds much flatter. But to my ears, there is enough of the bass coming through that I couldn't fully characterise this as a flat or neutral earphone.
So while the bass isn't ‘in your face', extension and control is very good for an earphone in this price bracket – it doesn't feel loose or bloated at all, and the overall emphasis on the bass is just enough to give tracks like ‘Gotham's Reckoning' from the Dark Knight soundtrack a bit of low-end energy that would be missing from a more neutral earphone.
With that said, the bass presentation is probably my favourite element of the B400's sound. I am less keen on the mid-range, though. It's quite clean and clear, but I have to say vocals – particularly female singers who usually have a luscious character to their voices, like Kat Gang and Stacey Kent – just felt a bit cold to my ear. What I mean by that is the B400 didn't give any warmth or emotion to vocalists, instead the mids just felt a little bit lifeless.
‘Lifeless' is perhaps too strong a word, but I am just trying to convey that these aren't the best earphones for listening if you want a warm, lush sounding mid-range. Admittedly the B400 mids do feel very transparent and clear, but for me that just came at the expense of a smoother and more emotional mid-range.
I mentioned at the start of this section that the overall sound of the B400 is ‘v-shaped', which means a bit of an emphasis on the treble too. For me, these earphones walk the line between ‘detailed' and ‘sharp' – for the most part, the high-end is resolving and adds a lot of detail to tracks, but it can be fatiguing at times. Of course, a lot of this is personal preference, while how well mixed the music you listen to is also a factor.
For instance, Owl City's latest album ‘Cinematic' is a very good example of a record that sounds great with the B400 – there is plenty of detail in the treble region without over-doing it and sounding sharp or sibilant. The high-end really complements the rest of the mix there. But switch over to something like ‘Messengers' by August Burns Red, and the treble proved to be just too much for me.
One thing I was not expecting to find when listening with the B400, though, is the sheer width of the soundstage. Simply put, for an earphone, this is undoubtedly the most spacious sound presentation I have heard. It's obviously not on the same level as a proper headphone like the HD 800 S, but it makes most other earphones I have used sound positively claustrophobic in comparison.
General separation and imaging is also very good, too – you get a very clear idea of where each different layer of the mix is coming from, so you can place the cymbals to the back-right, the snare drum just left of centre and so on. I have to say, the B400 is excellent in terms of its size and accuracy of its presentation.
These are very easy to drive, too – an impedance of 30Ω and the quite high sensitivity of 115dB means you will have no issues driving these from a phone. In fact, I did most of my listening with my Pixel 3 (with USB-C to 3.5mm adapter) and didn't go above 50% volume on the phone. A standalone amp is not needed for these.
Mic
The last area to touch on is mic quality – it is perhaps not a big factor in your buying decision, but it is worth testing since the default cable does have an in-built mic for conducting phone calls etc.
As you can hear from the short recording above – the less said about this mic the better. It's certainly audible, but the overall sound is very muffled and generally low quality. It will get you out of a pinch if required, but I'd rather use my phone's in-built mic.