OAE 2 - open over-ear headphones - Grell

Headphones - Open-Back - High-End - Made in Germany

There are products that improve an existing market. And there are products that challenge its basic assumptions. The grell OAE2 belongs to the second category. Axel Grell - the man whose signature is on some of the most important Sennheiser headphones of the last three decades, from the HD 600 to the HD 800 - has formulated a goal with his eponymous brand that no one in the headphone world has ever consistently pursued: to build headphones that adapt to natural hearing - not the other way around. The OAE2 is the first product of this philosophy to be developed for a wide range of specialist retailers. And it is different in every respect.

At its heart is Front Sound Field Modulation (FSFM) - an acoustic architecture principle developed by Grell in collaboration with the Leibniz University of Hanover, which directs the driver towards the ear at an angle from the front rather than from the side. Sounds like a detail. But its effect is revolutionary. Because where conventional headphones treat the auricle as an acoustic obstacle that colors the sound and locks the stage in your head, the OAE2 makes the auricle an active part of the sound experience - just as it always is with natural hearing. The result: voices are in front of you, not inside you. The stage detaches itself from your head. Music breathes.

Why does a good loudspeaker sound more spacious than good headphones - even if the headphones are technically superior? The answer lies in the auricle. When sound from a source hits the ear in front of us, the individual geometry of the pinna - its curves, folds and openings - shapes the sound through diffraction and reflection. The brain reads these subtle spectral delays and amplitude shifts, known as HRTF (Head-Related Transfer Function), and calculates precisely: Where is this sound source? Conventional headphones, whose drivers point to the side of the ear canal, skip this process completely - the pinna remains uninvolved, localization remains in the head.

FSFM makes the auricle a player again. The driver, sound guide and housing of the OAE2 are tuned in such a way that the sound front reaches the ear with early reflection and transit time differences, which the brain interprets as a frontal sound source. This is, as Grell audio emphasizes, not an effect, not a simulation and not a crossfeed filter - but an acoustic architecture that directly uses the natural physics of hearing. Early reflection cues and time differences are created in the same way as when listening to loudspeakers - only without a room and without ambient noise.

The sound character of the OAE2 follows the school that Axel Grell has shaped over decades: neutral at the core, with subtle warmth in the fundamental tone for body and substance. Mids are expressive and textured, voices are realistic in size and stand in front of the listener, not inside them. Sibilants remain natural, the highs resolve finely without sparkling or piercing. The bass is deep and has a particularly physical presence in the mid-range - according to the independent test by headphonecheck.com, the level is between the OAE1 and a Sennheiser HD 650, with noticeable power and visual plasticity that only fully unfolds at a sufficient listening volume. If you test the OAE2 at half volume, you won't hear what it can do.

The decisive strength lies in the room. Live recordings create a concert atmosphere that can hardly be compared with the Sennheiser HD 660S or Hifiman Sundara - the hall seems bigger, the stage wider, the connection to the action more immediate. At the same time, the OAE2 remains direct and involving despite the deep stage in the room - no detachment, no cool analytics, but intense involvement. It reveals its most convincing side with vocal music, jazz and classical chamber recordings: voices breathe, bow movements are in the room, the climate of a recording becomes tangible. If you love loudspeakers but often use headphones out of consideration for your neighbors or family, the OAE2 is the emotional bridge between the two worlds.

An important note for new owners: The OAE2 takes some time to get used to. If you compare it directly with conventional headphones, you will initially hear the unfamiliar - not the better. Grell audio expressly recommends spending one or two listening sessions exclusively with the OAE2 before making a comparison. Owners consistently describe what then happens: the previous favorite headphones then seem smaller, narrower, less real.

The OAE2 uses dynamic 40 mm drivers with a bio-cellulose diaphragm - a material that is known for its balance of stiffness, weight and internal damping and has been used in audiophile headphones for decades. The low impedance of 38 ohms makes the OAE2 versatile: it sounds convincingly spacious when connected to a stationary headphone amplifier of the class of a Lehmann Audio Linear - responds to higher output voltages with a measurable gain in stage width and depth, but can also be operated directly on mobile devices or laptops. Fully balanced operation via the supplied 4.4 mm connector is already possible ex works.

Compared to its predecessor, the OAE1 - which was previously sold exclusively via the US platform drop.com - Grell has made three specific improvements to the OAE2: The ear and head pads have been redesigned for improved fit and long-term comfort. The adjustment range of the headband has been increased to securely cover more head shapes. And the frequency response has been fine-tuned - the bass has been slightly tightened compared to the OAE1 - for an even better sound balance between richness of detail and naturalness. The OAE1 is not being replaced; both models retain their independent credentials.

The open stainless steel mesh housing - the design is based on the iF Design Award-winning OAE1 Signature - combines industrial precision with an open, architectural aesthetic. At 378 grams, the OAE2 is no lightweight, but the weight is evenly distributed thanks to the velour memory foam padding and the wide headband: Hours of fatigue-free listening is possible without pressure points. If you wear glasses, you should make sure that the pads fit securely when you first put them on - minimal displacement can affect the stage height.

The modular design allows ear and head pads, cables and other components to be replaced without tools or specialist service - a conscious statement against the throwaway culture in the headphone market. Grell audio produces in certified production facilities, dispenses with plastic packaging and plans the OAE2 as a long-term, repairable product. An optional clip-on microphone boom is available as an accessory, which transforms the OAE2 into a fully-fledged headset.