Manufacture Discription:

One of the highest efficiency planar phones in the world! HIFIMAN’s newest HE400S sounds terrific on your smartphone or most any portable audio device.

HE400S delivers all the lifelike clarity, detail, extended bass and wide sound stage that audiophiles have come to expect from HIFIMAN.

Innovative headband and specially designed ear pads for remarkable comfort allowing you to enjoy your music for hours on end

Dynamic headphones utilize conductors that vibrate in limited areas of the diaphragm. Result is that a large percentage of the diaphragm cannot be directly driven by those conductors.

Planar headphones have conductive layers over almost all of the diaphragm. Evenly driven by these conductors, result is significantly lower distortion than conventional dynamic headphones.


Finding the right pair of headphones is no easy task. From the basic ones to the high-end product line, choosing the right headphone means knowing the exact audio output that you want along with the features it supports.

Hifiman’s HE400S may be the lesser priced among the premium headphone range, but it easily is one of the best performing headphones we’ve tested for its price. Let us go have a look.

Manufacturer’s Specification:

  • Frequency Response: 20Hz – 35KHz
  • Sensitivity: 98dB
  • Impedance: 22 Ohms
  • Weight: 350 g
  • Cable Length: 1.5 m
  • Plug: 3.5mm/6.35mm

Design and Setup

The Hifiman HE400S offers the same level of quality and detail that one can expect from the well-loved brand. The headphones feature a lightweight design – and at only 350 grams it’s comfortable to wear even for long periods of time.

Design-wise, the Hifiman HE400S has an arch with a headband pad to aid in a more comfortable fit. There are grill-like designs present on each ear cup, giving it a somewhat unique appearance.

Additionally, the Hifiman HE400S utilizes Planar technology that uses conductive layers on the headphones diaphragm. This results in a lower distortion compared to more conventional dynamic headphones.

The headphones, while it doesn’t completely isolate outside noise, does the job in providing a listening environment that is enough for you to enjoy the various melodies no matter the environment. The package includes a detachable braided audio cable and headphone adapter.


Excellent isn’t enough to describe the Hifiman HE400S’ performance. For testing, I hooked up the headphones to the iFI nano iCAN and then to my smartphone for listening to my music library.

Tonal clarity is perfect, along with perfect mids and has all the good low-frequency traits of a planar magnetic headphone; tight, refined and responsive,very deep. Even at high volumes, I didn’t experience any sort of distortion when using it. There is a certain sense of smoothness to the tunes, and that happens with each presentation.

Additionally, stereo separation is perfect, and even non audiophiles will find something to love about the Hifiman HE400S. Each channel is carefully tuned and placed, and I was in euphoria by simply listening the headphones for hours.

The HE-400S has an impedance of 22 Ohms and a sensitivity of 98db. Though a standard smartphone is capable of driving these

Supplied Accessories:

  • ¼” (6.35 mm) headphone adapter
  • Headphone Cable (1.5 meter or 4.9 Feet; 3.5mm plug)
  • Earpads:1 pair (on the headphone)

Pros & Cons:


  • Comfortable fit and great build quality
  • Decent tuning and excellent bass


  • None to mention


The Hifiman HE400S is already inexpensive for its $299 price, considering it’s more than just the normal headphone. Its performance is something worthy of our praises, and even if isn’t the best performing headphones around, it still manages to give us a decent unforgettable listening experience.