This is the place to discuss all things HE-X4.
I’ve had the opportunity to spend some time with Drop’s latest entry level budget planar, the HE-X4 after having done a full review of HiFiMAN’s latest release, the HE400se. The following will be a reference point for all the measurements I’ve done on it and my findings so far.
Drop X HiFiMAN HE-X4 Frequency Response:
So, this should look super familiar to anyone who’s seen measurements of the recent HiFiMAN HE400se. That’s because they sound essentially the same. Now, it turns out that they are in fact NOT using the same drivers - at least for the international version of the HE400se. But interestingly enough, the transducer difference doesn’t seem to matter for these headphones in particular.
As mentioned, that’s close enough to where you could imagine it being L/R of the same headphone, with any slight differences being down to channel or positional variation - but these are actually two different headphones.
Now I should explain that I was also initially under the assumption that the HE-X4 and the HE400se were the same headphone acoustically because the drivers physically look nearly identical, all the way down to the glue on the magnets being the same pinkish color.
Pretty similar, right? You can see why I initially made this assumption. But if you look closely, you can see that on the HE400se, the magnet bars are rounded on the edges, while the HE-X4’s are not. This is HiFiMAN’s ‘stealth magnet’ tech in practice on the HE400se.
You can see it even more clearly when taking the grille off the back of the housing and holding them side by side. Incidentally, both headphones use double-sided magnet arrays for their design, but make no mistake, this is only one parameter for planar transducers. Double-sided is by no means an indicator that it’s better than single-sided designs. You can have good and bad instances of either type.
Now, getting to the stealth magnets… I’m told that conceptually this is intended to do similar things to what Audeze’s fazors do - and HiFiMAN have implemented this in some of their ultra high end headphones as well. But in practice, for these two headphones specifically, there doesn’t seem to be any meaningful difference. So while the drivers are different, I do not hear any difference between the two. Neither for tuning/frequency response, nor for subjective performance.
So I think the interesting thing here is that given the other parameters that exist with these two headphones, the stealth magnet implementation probably isn’t necessary. Now to be clear, I’m not saying this concept doesn’t make a difference, and maybe it makes an audible difference for their other headphones that have different parameters, but in the case of these two specifically, it’s a wash.
Here are some of the additional results that tipped me off that the drivers were in fact different.
HE-X4 THD (@100dB):
HE400se THD (@100dB):
Air gap differences (HE-X4 = Blue Dotted, HE400se = Brown)
It’s all similar and very… familiar, but different enough that it caused some head scratching. In both cases for THD I don’t think any of that stuff would be audible. It was taken at 100dB after all, and nobody is listening that loud (ideally). This is mainly just to see how it behaves when cranked up to potentially find any differences. And with the air gap stuff, it’s around the same spot, but there does seem to be some difference in overall level there.
Anyway, the conclusion here is that they’re both decent for the price, and the same EQ I used for the HE400se can be applied to the HE-X4:
Now if anyone is wondering how the HE-X4 and HE400se perform for their ‘technical qualities’, they’re generally solid for the price. They don’t suffer from too much haziness or graininess, nor the somewhat smeared effect of many other entry level planars. But at the same time, they are a little bit on the ‘sluggish’ side of things for the attack and initial leading edge transients. Soundstage is decent, definitely better than the Sennheiser HD6XX, but maybe not as evenly distributed as on the Sennheiser HD560s.
Overall, these both sound pretty good for the price. They’re both a bit lean in the sub-bass, and they both have the typical 2khz dip that HiFiMAN headphones often have. But on the plus side, the treble presentation is decently smooth.
I’ll summarize it like this:
- Comfort - HE400se > HE-X4
- Weight - HE400se > HE-X4
- Aesthetics - HE-X4 > HE400se
- Cable - HE-X4 >>>> HE400se
- Sound Quality - HE400se = HE-X4
Which one is better? Well if it’s me I’d go for the HE400se due to the better headband and it’s about 30g lighter so it’s more comfortable. But at $129 the HE-X4 is the better value, especially because it comes with a cable that’s not at all terrible, which is something I can’t say about the HE400se.