Performance

HiFiMAN has done a good job at maintaining the HE-400's looks with the S-model. That characteristic arch-type headband is still there and works just as brilliantly as on other HE-series headphones. In terms of listening comfort, the HE-400S is perhaps marginally better than the rest of the HE-series due to its lighter weight and full velour pads, instead of the hybrid pads we have seen on the HE-400i and the HE-560.


When it comes to sound quality, it is clear that the HE-400S is a good step above the HE-300 that was priced similarly at its launch. The planar characteristics in the lower mid-range and bass area are more or less intact even though several things have been dialed back to bring its cost down. The bass is still quite impressive and will be a though job for any sub-$300 headphones to match in terms of speed and attack.

The bass and lower midrange is well integrated - there are no obvious bumps or oddities except for a slightly longer decay than we are used to from HiFiMAN's modern planar magnetics. This is due to the internal design as a change of pads did not alleviate the issue audibly with our gear. The decay may be due to the drivers being approximately 25% more efficient than those on the HE-400i.

The midrange is still very well controlled, but is not as resolving or open as with the HE-400i or HE-560, which is widely regarded as having one of the best midranges on the market today. While sounding somewhat veiled compared to the HE-400i, it is nothing compared to the veil on the Sennheiser HD650. The HE-400S is more resolving throughout than the Sennheisers, which is good as those two headphones trade at roughly the same price these days. The fact that they do not sound as airy might be because they have a slightly less emphasized upper midrange. The HE-400S has an extremely well-balanced frequency response overall, which makes it perform very well with all types of music.

Compared to its bigger brethren, the HE-400S's soundstage is a little less precise in its projection, though still good for the price. Upgrading the pads to the Focus pads from HiFiMAN definitely ups this performance aspect noticeably, but the pads are also quite expensive. The Focus hybrid pads are also less comfortable, so you have to find your golden middle path.

The amplification requirements are much lower for the HE-400S, compared to other HiFiMAN planar magnetic headphones. Due to its more efficient drivers, you can go all the way with a normal sound card. The STX II powers them beautifully. The C5D from JDSLabs we use as a benchmark here will net you a small gain, but the gain is more subtle than on other higher-end headphones we have tested of late.