THIEAUDIO Cypher Review: Audiophile open-back headphones

The THIEAUDIO Cypher is THIEAUDIO’s first serious attack on the high-priced headphone market and this attack is on target. For around 399 US dollars, you can get open-back headphones with 50 mm dynamic drivers that will make even much more expensive competitors sweat in terms of workmanship, comfort and sound. The headphones are currently available as part of a Kickstarter campaign.

Technical data of the THIEAUDIO Cypher

The product	Cypher
Type of construction	Over-ear
Acoustic construction	Open-back
driver	50mm
Transmission type	Wired
Ear pad material	velour
Impedance headphones	32 Ohm
Transmission range	20 – 20,000 Hz
Price from	from 329,00 USD

THIEAUDIO Cypher Review: Design and workmanship

When you pick up the THIEAUDIO Cypher for the first time, you immediately realize that no compromises have been made here. The entire housing is made of solid aerospace aluminum. Precisely CNC-milled, with a smooth, seamless surface that is both visually and haptically on a level that you simply wouldn’t expect in this price range. Even after weeks of intensive use, the material still feels flawless, shows no scratches and has a high-quality appearance throughout.

The headband is made of a composite material made of stainless steel with a carbon fiber-like surface treatment. Light as a feather and yet exceptionally stable. The underside of the headband is lined with genuine Coby lambskin, which is pleasantly soft to the touch and, unlike synthetic leatherette, does not crumble or peel after a few months. Anyone who has ever used inexpensive headphones with protein leather padding in a warm climate knows how much this detail is actually worth. The THIEAUDIO Cypher focuses on real longevity here.

The ear pads deserve a special mention: they are made of memory foam with a velour cover that adapts to the individual head shape and ensures a comfortable, fatigue-free fit even after hours of listening. The pads are attached using an elegant magnetic system. A short, firm click and the pads fit perfectly. Removing and reattaching them is child’s play, which makes cleaning and any replacement much easier. Removing the pads reveals the angled drivers, which gives an idea of the meticulous engineering work behind them.

The ear cups can be swiveled a full 180 degrees. With a pleasantly firm resistance that reliably holds the set position. This is not a wobbly plastic mechanism, but a precisely milled pivot point that fully serves its purpose. The temple is infinitely adjustable in size via lateral sliding rails, which do not show any signs of fatigue even after frequent adjustment.

As far as the look is concerned, the Cyphers look like professional studio equipment. Clear, functional, without superfluous design gimmicks. The open design of the ear cups with their aluminum grille gives the headphones a technical character that underlines their intended use. Despite the all-metal construction, the weight is surprisingly low. The weight distribution is so well balanced that the headphones are literally forgotten in everyday use.

Audiophile features in the Cypher

The THIEAUDIO Cypher come in packaging that fully lives up to the product’s premium claim. The unboxing experience is well thought out: the headphones are safely stored in a high-quality leather transport case that offers enough space to lay the headphones completely flat. A seemingly small detail that turns out to be surprisingly practical in everyday life, as the headphones can be easily stowed away in a bag.

The scope of delivery includes a 1.5 meter long, braided cable with a fabric sheath, which is pleasant to the touch and has no memory effect. The cable ends in a 3.5 mm jack plug. A 6.3 mm adapter is also included to ensure compatibility with headphone amplifiers, DACs, mixing consoles and professional playback devices. This results in broad connection compatibility.

The heart of the equipment is the newly developed 50 mm dynamic driver, which is technologically at a level not expected in this price range. The driver relies on a 20-pole N45 magnet system, which delivers exceptional driving force and precise control over the cone. The diaphragm itself is made of a semi-crystalline polymer-rubber composite material that optimally balances stiffness and damping: stiffness for clear, low-distortion transmission, damping to suppress unwanted resonances. The voice coils are made of a high-voltage-resistant copper-aluminum alloy – a detail that sounds technical on paper, but has a clearly perceptible effect on impulse response and detail resolution in the listening test.

The acoustic chamber of the Cypher was also manufactured using CNC milling, which ensures an exact and reproducible geometry of the sound space. THIEAUDIO has incorporated almost a decade of audio perception studies into the development of its own reference tuning target. A rarity in the market for headphones under 400 euros.

As open over-ear headphones, the Cypher is clearly designed for stationary use: at home, in the home studio or at the desk. The open design enables a more natural sound space and better spatial imaging, but at the same time is not suitable for mobile use in public spaces as it does not shield outside noise.

THIEAUDIO Cypher: Operation

The THIEAUDIO Cypher are purely passive, wired headphones. This means: no Bluetooth connection, no touch control, no app, no volume buttons. If you’re looking for active noise-canceling functions or voice assistants, you’re in the wrong place here. But this is a deliberate choice: The Cypher is aimed at users who prioritize maximum sound quality over a convenient feature set.

In everyday use, the connection cable proves to be pleasantly uncomplicated. The 3.5 mm plug is located on the left-hand side of the headphones and is easy to connect and disconnect. The 1.5 meter long cable offers sufficient freedom of movement in a studio context. If you use the headphones at your desk, you can easily stand up without disconnecting the cable. The cable sheathing is hard-wearing and shows no signs of wear after intensive use.

Putting on and taking off the headphones is intuitive. The headband with its lambskin leather padding sits so comfortably on the head that even hours of listening sessions remain without pressure points. The ear cups close gently around the ears and exert pleasantly little pressure. Changing the ear pads is done in seconds thanks to the magnetic system. No screwing, no clamping, no awkward pulling. For users who regularly clean their headphones or want to try out different cushion variants, this is a real gain in everyday practicality.

As the Cypher has an open design, ambient noise reaches the ear more unfiltered than with closed designs. At the same time, the headphones emit sound to the outside. This is not a problem in quiet home environments, but can quickly attract unwanted attention in office environments or public spaces.

Audio quality of the THIEAUDIO Cypher

After extensive listening sessions over several weeks, it can be said that the THIEAUDIO Cypher is the rare case of a headphone that lives up to its own claim as a studio reference and never sounds dry or lifeless.

The low-frequency range follows a 5 dB bass boost between 20 Hz and 300 Hz, which THIEAUDIO has deliberately built in as the foundation of the sound image. At first this sounds like an excessive emphasis on bass, but in practice it proves to be cleverly calibrated: The bass reaches deep down and conveys physically perceptible low bass impulses, but remains tight, controlled and completely free of the diffuse veil familiar from poorly damped bass designs.

Compared to the legendary Sennheiser HD600, for example, the Cypher has a clear advantage: while the HD600 is noticeably weaker in the sub-bass range, the Cypher delivers real resolution and substance there. Anyone listening to electronic music, jazz double bass or orchestral works will notice this difference very quickly.
The mid-range is the Cypher’s flagship: completely linear, warmly neutral and very natural.

Guitars, pianos, wind instruments: all instruments sound present and authentic, with a timbre fidelity that is ideal for mastering and monitoring work. The sound is reminiscent of the strengths of the HD600, but goes one step further in terms of technical resolution. The treble range is balanced, neither too dark nor too bright. It is energetic enough to give transients crisp contours, but remains free of sibilance or signs of fatigue after prolonged listening. The reproduction of fine details is remarkably precise for a dynamic driver in this price range.

A note: The Cyphers scale with better amplifiers. They already sound really good from the smartphone output, but only develop their full potential with a dedicated headphone amplifier or a high-quality DAC/amp combination device.

Read more: beyerdynamic DT 990 PRO X test: Open champion?

THIEAUDIO Cypher Review: Conclusion

These headphones are a serious challenge to the market. The build quality is simply impressive: all metal, with genuine lambskin leather, magnetic pads and a driver that has had almost a decade of research put into it. The sound tuning will strike a chord with those looking for both musical pleasure and professional reference in one device. Warm enough for long listening marathons, precise enough for critical monitoring.

In a direct price comparison, the Cypher stands out in particular: if you are looking for comparable materials, driver technology and sound quality, you often have to dig much deeper into your pockets with other manufacturers. The Cypher delivers an experience that is normally reserved for devices in the four-digit euro range.

There are some minor limitations: A balanced cable would have been desirable for audiophile users, and the headphones reward investment in a higher-quality signal chain. If you use it with a smartphone, you will hear well, but not at the level that the Cypher is capable of. In addition, the open design is clearly geared towards home use.

For audiophiles, studio musicians, mixing engineers and discerning home listeners looking for neutral headphones with first-class build quality, the THIEAUDIO Cypher are one of the most convincing recommendations in the under 400 euro class.

PRO