With the synergistic effect of a hybrid design that merges balanced armature with a 50mm diameter dynamic driver unit coupled with BAM mechanism, we’ve achieved an extraordinarily vast sound stage. The music fixed inside our heads with headphones up until now vibrates in a vast space from side to side and with depth.

With balanced armature driver units, iron is driven to produce sound, and as such, these drivers face a number of problems, amongst which are “proving tiring to listen to”, “having sound that is subtle and beautiful, but lacking in depth and being flat” and “lacking bass interval”. At final, we decided to focus on developing technology for the reproduction of bass tones and three-dimensional space with the full-range reproduction of a theoretically unproblematic single driver unit, rather than taking things in a multiway direction. We went back to the beginning and reviewed the performance of the balanced armature driver, focusing our attention on something we had previously overlooked ? airflow inside the housing. We developed BAM (Balancing Air Movement), a mechanism that optimizes airflow inside the housing through the creation of an aperture in the driver unit, which is usually sealed.

While achieving bass tones and deep, three-dimensional spatial representation, which proved difficult with single driver full-range reproduction, we achieved a BA type that at the same time made for natural listening the user doesn’t tire of.

Balanced armature driver unit developed by our company for optimal use as a tweeter. We’ve paid special attention to our choice of materials used in our pursuit of sound quality, utilizing a permalloy with a high level of magnetic permeability in the magnetic circuit.

A driver unit with a diameter of 50mm, newly designed for SONOROUS. By increasing the precision of the parts, it has become possible to make the gap between the magnetic circuit, the pole piece and the yoke narrower than with common products. A powerful neodymium magnet is coupled with this,
making for a high magnetic flux density. The result is clear sound quality.

We’ve re-examined the shape of the tangential edge and have employed a lightweight diaphragm with a heightened responsiveness to micro-signals.

The voice coil is copper-clad aluminum wire CCAW. Clear, crisp bass tones are achieved with the combination of a magnetic circuit with a high driving force and a light vibration system.

So as not to inhibit the sound emanating from the driver unit, and so that there is no unnecessary added reverberation, a form that is as slim yet as strong as possible has been pursued. This contributes to clear
sound quality.

In combination with the ABS housing is the machined stainless steel housing that reduces unnecessary vibrations. To demonstrate maximum results, it is necessary that both are machined with the utmost accuracy, and as such, the stainless steel has also been machined. The surface is finished with the tool marks from the machining process left as is. They are machined domestically at a leading specialty machining factory. Taking sufficient time and using extremely finely edged tools, this careful manufacturing is teeming with the knowhow of Japanese craftspeople.

What plays an important part in sound quality is the fit between the user’s ear and the ear pad. If there is space between the two, then bass tones are lost; if the ear pad presses against the user’s ear with too much pressure, then apart from it being uncomfortable, the acoustic pressure of the bass tones rise too high, resulting in negative influences on sound quality. In spite of this, there was no evolution seen in the ear pads on the market, and they continued to be made using the same structure for many years.

We got engineers who had been involved in the development of corsets to participate in developing our ear pads, and re-examined the fit between the user’s ear and the ear pad. By employing the appropriate technology – pursuing synthetic leather with the best elasticity and the best sponge cutting and adopting ultrasound fusion for the adhesion of the synthetic leather to the inner frame – we constructed an unwrinkled, three-dimensional form with just the right amount of tension to it.

A 1.5mm thick aluminum back plate at the back of the driver unit for achieving air pressure balance. Not only air pressure balance but also great results in the suppression of unnecessary vibrations are manifested.

To achieve a high level of accuracy with the extremely hard, texture casting finished ABS housing, which is also used with high grade camera lenses, simulations were carried out until the appropriate level of fluidity with respect to the molding materials was achieved. Realizing high circularity led to the realization of a highly accurate fit with the machined stainless housing. To put the concept of reducing unnecessary vibrations through the combination of different materials with different resonance points into practice, ingenuity has also been exercised in those sections that are not readily visible.

We employed a gold-plated monaural plug with a 3.5mm diameter for the connector on the headphones. By employing a connector with a long-standing performance record, we avoided any trouble resulting from poor contact owing to deterioration due to aging. The cable has a locking mechanism that rotates 90 degrees.

Detachable cable with locking mechanism (1.5m)

Hybrid-like headphones that produce sound having both the virtues of dynamic types and the virtues of BA types. Clear high frequencies spread across a vast sound field just as they would with open type headphones. Thanks to the stainless steel housing, the rise in the sound produced is good, and is suited to a variety of music genre.