On top of the driver revisions, HiFiMAN added a few subtle, but important, stylistic changes to the HE-400. The first change that I noticed is possibly the hardest one to spot at first glance. On the original HE-400, the metal ear cup supports, which allow listeners to adjust the ear cups vertically to match their head size shape, are polished to a smooth finish (you can feel this by running your finger over the surface of the metal). Aesthetically, the smooth finish looks wonderful, but I noticed that the ear cups would tend to unintentionally slip vertically when I moved my head and I gathered it was because the finish of the metal created too little friction. On the Rev 2 HE-400s the metal supports look almost identical to those used on the original version, but when you run your fingers across the surface you will feel that a subtly textured surface has been added, which really helps the ear cups stay in place once you’ve picked out the right fit for your head. In fact, the texture has added so much friction that listeners will have to apply more force than they’re anticipating to make the ear cups slide vertically.
The second design change to the HE-400 is the termination plug. On the original HE-400 the signal cable was terminated with a standard ¼” phone plug, but also came with a rather bulky, slip-on ¼” – 3.5mm mini-plug adapter. On paper this looks like a good idea but in practice the entire plug assembly is over 5” long once the 3.5mm adapter is installed, which makes it relatively cumbersome. When you consider that the HE-400 is sensitive enough that it can be driven directly from an iPod or iPhone, it made no sense for the mini-plug adapter to be so large. The Rev 2 version of the HE-400 addresses this problem by doing two things. First, the signal cable is now fitted with a standard 3.5mm mini-plug and can be converted to a ¼” plug via an adapter. Second, the entire plug assembly (3.5mm plug plus the ¼” adapter) is now down to a much more compact 3” length. Overall, this set-up is much more manageable and looks more pleasing to the eye.
HiFiMAN’s Revision 2 version of the HE-400 takes what was already an exceedingly easy-to-drive planar magnetic headphone to the next level sonically. Specifically, the new drivers transform the dark and moody tone of the original HE-400, giving the headphone a much more neutrally balanced, audiophile-friendly frequency response curve. On top of the revised drivers, HiFiMAN has also upgraded the metal supports for the Rev 2 headphone’s ear cups as well as its signal cable termination plug layout. Both changes add style and increased functionality to the HE-400. Inexpensive, easy-to-drive, and now more neutrally balanced… What else could you ask for?
HiFiMAN HE-400 planar magnetic headphone with Revision 2 Drivers
Accessories: Fabric drawstring-type carrying bag, 3.5mm mini-plug to ¼” phone plug adapter.
Frequency Response: 20Hz – 35 kHz
Sensitivity: 92.5 dB
Impedance: 35 Ohms
Weight: 14.5 oz.