Hifiman HE6se

The Hifiman HE6se builds on the foundations of the HE6, a planar magnetic headphone launched in 2010. This edition uses the same drivers as the original model, combined with a redesigned, lighter frame. Its low sensitivity implies substantial power requirements, a characteristic already present on the HE6. The HE6se also retains the gold-coated diaphragm of the initial model. It is intended for users with amplification capable of meeting its demands.

Planar drivers with gold diaphragm

The HE6se uses planar magnetic drivers of around 60 millimeters in diameter. Unlike conventional dynamic drivers, where a voice coil attached to the center of a conical diaphragm generates sound, planar drivers rely on an ultra-thin flat diaphragm onto which electrical conductors are directly deposited. This diaphragm is suspended between two arrays of magnets arranged to create a uniform magnetic field, known as isodynamic.

When an electric current passes through the conductors on the diaphragm, it generates its own magnetic field that interacts with that of the permanent magnets. This interaction causes the diaphragm to move across its entire surface, in a uniform and controlled manner. This design helps limit harmonic distortion and achieve a very fast transient response, as the diaphragm reacts instantly to variations in the electrical signal.

On the HE6se, the diaphragm features a gold coating. Dr. Fang Bian has praised the use of a “quasi-nanometer-grade” diaphragm covered with a thin layer of gold. This process, also used on the high-end Susvara, aims to optimize electrical conductivity while preserving the lightness of the diaphragm. The gold forms the conductive traces that run across the surface of the diaphragm and allow current to flow efficiently. This characteristic gives the HE6se a distinctive visual appearance when observing the drivers through the perforated earcup grilles.

Sensitivity that challenges amplifiers

With a sensitivity of 83.5 dB and an impedance of 50 ohms, the HE6se ranks among the most difficult headphones to drive on the market. To reach a comfortable listening level around 85 dB with sufficient dynamic headroom, you should count on about 1 to 1.5 watts per channel. Hifiman officially recommends a minimum of 2 watts at 50 ohms to fully exploit the headphone. In practice, many users report that the HE6se performs at its best with amplifiers capable of delivering 4 to 6 watts, or even more.

This particularity has led some owners to connect the HE6se directly to speaker amplifier terminals. Hifiman anticipated this practice by including the HE adapter, a resistor box that allows you to safely connect a power amplifier to the headphone via a 4-pin balanced XLR output. Using such an amplifier, however, requires a preamplifier or a volume controller upstream, as most power amplifiers do not feature a volume potentiometer.

A modernized and practical frame

The HE6se adopts the suspension system and headband used on the Sundara and Ananda. This structure combines spring steel, aluminum alloy, and synthetic leather, with a black matte and anodized silver finish. The suspended leather headband distributes the weight on the top of the head more evenly than the narrow, rigid headband of the original HE6. Height adjustment is stepped, with a firm mechanism that holds the chosen position well, though some users find this system less refined than on more expensive headphones.

Perforated earcups house the planar drivers. Hifiman has opted for quality plastic and metal, with perforated grilles that reveal the golden drivers. The open-back design guarantees zero isolation: the HE6se lets in all ambient noise and leaks a lot of sound outward. The angled leatherette earpads are deep enough for most ears, although comfort remains subjective.

A notable difference from the original HE6 concerns the connectors. Hifiman has abandoned the screw-on coaxial system of the HE6, often criticized for its fragility, in favor of two 3.5 mm jacks angled at 10 degrees at the base of each earcup. This choice greatly facilitates cable replacement and broadens compatibility with third-party cables, including those designed for other Hifiman headphones, certain Beyerdynamic models, or Meze.

The HE6se comes with a cable terminated with a 4-pin XLR plug on the source side and two 3.5 mm jacks on the headphone side. A 4-pin XLR to 6.35 mm jack adapter is also provided for amplifiers equipped with a standard single-ended output. Hifiman also includes the HE adapter, allowing the headphone to be connected to a speaker amplifier via the output terminals. The whole set is presented in a leatherette-covered box, which looks more like a jewelry case than a simple headphone package.

A reference headphone for established setups

The HE6se does not claim to be versatile. Its extremely low sensitivity reserves it for users who already have suitable amplification, whether high-power headphone amplifiers or integrated or power amplifiers for speakers. The investment in a suitable amplifier can quickly exceed the price of the headphone itself, which explains why the HE6se mainly appeals to those who have already taken that step.

For listeners looking for a planar magnetic headphone without the amplification constraints of the HE6se, Hifiman offers more efficient models such as the Sundara, the Ananda, or the Edition XS. These headphones offer much higher efficiency and can work properly with portable amplifiers or entry-level desktop DAC/amps. The HE6se is aimed at those who want to rediscover the characteristics of the original HE6 without having to hunt down a used model, or who already own the necessary amplification and are looking for a headphone capable of exploiting that power.

The HE6se’s frequency response extends from 8 Hz to 65 kHz, well beyond the audible range. This extension into the extreme lows and highs reflects the ability of planar drivers to faithfully respond to a very wideband signal. In practice, the HE6se’s low-frequency reproduction is often described as physical and well-defined, with deep extension that can be surprisingly impactful on certain recordings. The midrange benefits from the low distortion inherent to planar drivers, while the treble takes advantage of the diaphragm’s speed to reproduce transients with precision.

Technical Specifications

Design

• Type: Open
• Coupling: Circumaural
• Weight: 502 g

Audio Performance

• Impedance: 50 Ω
• Frequency Response: 8 Hz - 65 kHz
• Sensitivity: 83.5 dB