When Technics set about making plans for its new flagship wireless headphones, the EAH-A1000, it knew it couldn't just enlarge the 10mm Magnetic Fluid Driver used in the five-star, Award-winning EAH-AZ100 wireless earbuds and call it a day.
The magnetic fluid technology – an oil-like substance with magnetic properties that reduces the rocking vertical movement of the diaphragm without adding mass – worked successfully in delivering a clear, detailed and low-distortion sound in the AZ100 buds. But the larger 40mm drivers required in an over-ear model proved a greater challenge.
As part of the pre-launch briefing of Technics' new EAH-A1000 over-ear wireless headphones, I got a chance to hear from Technics' headphones and acoustic departments in Tokyo about the trial-and-error process for developing the new flagship headphones' drivers, along with an extensive look at all the elements inside them – so here's a closer look at the new drivers of the A1000 headphones.
Magnetic fluid driver: the next chapter
Planning for the EAH-A1000 over-ears started pretty much after the AZ100 buds, with the question: "Can magnetic fluid work in a 40mm driver?"
A larger driver results in greater excursion, more possibility for flexing, and more scope for distortion. Simply using the same tech in a bigger driver "didn't deliver the sound we were aiming for," says Technics. The magnetic fluid sits between the voice coil and driver magnet, and is able to precisely support the driver's movement so it is more consistent, but too much damping could limit the natural expression of music.
While excited by the potential of the magnetic fluid technology, Technics' goal wasn't to simply build a larger driver, says Riku Takeda, acoustic engineer at Technics. It was to "create a new over-ear headphone driver that could go beyond hi-fi speaker performance."
The main aim for this new driver was to reduce distortion as much as possible for a clearer, cleaner sound, but without sacrificing the power, detail or natural resonances of music. And so the newly developed 40mm drivers in the A1000 feature a combination of technologies, all with the aim of delivering an immersive listening experience.
The first of these new technologies takes inspiration from the brand's own hi-fi speakers, with the modified magnetic fluid drivers enhanced with an SST (Symmetrical Surround Technology) Edge. This is a similar technology used in Technics' flagship SB-R1 speakers.
This surround's distinctive shape ensures that the same volume of air is displaced by the backward and forward movement of the driver. The cuts in the surround increase the flexibility of the edge, while also reducing distortion.
"No compromise on shape; no compromise on material"
Additionally, the diaphragm of the driver is made of a "pure carbon fibre" material, chosen for its lightweight and rigid properties that ensure fast, responsive performance. Technics further clarifies that this 'pure' carbon fibre material isn't composed exclusively of carbon fibre, but it refers to a "non-composite, non-laminated" diaphragm construction. A very thin but stiff layer, essentially.
As larger drivers naturally flex more as they move, Technics settled upon a complex shape consisting of a cone and a raised dome to further stabilise the movement of the driver.
This posed another challenge, as the mould for this complex geometry (in the relatively small dimensions of a headphone driver) was difficult to produce in mass quantities consistently without deformations.
The team experimented with alternative shapes and materials to get a more stable, consistent moulding, with a long trial-and-error process – but every 'solution' resulted in a less-than-ideal sound. A flatter cone geometry would make things simpler, but it resulted in a less powerful, muddier and less clear sound. A laminated structure would improve moulding stability, but it delivered a narrower soundstage compared with the pure carbon fibre material.
Ultimately, Technics decided that the compromises to the sound quality were simply "not acceptable to us", and ploughed ahead with these two necessary elements of the complex shape of the diaphragm, with some solutions, to achieve the desired sound that Technics wanted. This included strengthening the carbon fibre material itself by changing the direction of the fibres woven in, and adding a 'rib' to the dome to add stability.
Technics says it's a combination of all these different technologies, not just one element, of the new driver that is key to delivering accurate bass, clear highs, and a natural spatial expression from the A1000 headphones.
The development doesn't stop at the drivers themselves. The new 'baffle flat structure' minimises the uneven surfaces around the driver to reduce the effect of unwanted reflections, while an 'acoustic control chamber' behind the driver helps to manage airflow.
These combine to deliver a "natural sound field with clear imaging" and to ensure the sound is balanced without emphasising any specific frequency range.
Sound quality is just one aspect of the Technics EAH-A1000. Every product in Technics is guided by three philosophies: sound, technology and design.
The design of the headphones and all the necessary features (connectivity, ANC, call quality) need to be up to scratch, too, with Technics acknowledging that "personal audio" products such as headphones have huge demands from customer expectations these days. Over-ear headphones are more visible than earbuds, too, so achieving the design and style of the premium A1000 to a high level became even more important.
The design of the new over-ears – from the slender 'flow arm' structure, the headband's clamping pressure, and evenly distributed plush memory foam cushions – has been given as much care and attention by the Technics team.
We're shown various prototypes of different ear cushion shapes, arm structures and variations in the spun metal plate with the Technics logo adorned (check out the gallery above) – examples of more trial-and-error processes undergone by the design team to achieve the 'right' look and feel for the EAH-A1000 headphones.
The philosophy remains the same
Ultimately, though, anything that affects sound quality will need final approval by the acoustics team, as for Technics, the sound philosophy is most important.
"If sound quality isn't achieved to our high standard level, we don't bring it to the market," says Technics. Every audio product, including the EAH-A1000, is subject to the approval process by Technics' internal Sound Committee, which includes Yu Tanaka, who was responsible for the magnetic fluid driver in the A1000 and set the targets for the headphones' sound quality, and Technics' brand director Michiko Ogawa, who has the final say. If those sonic targets aren't met, they would simply postpone the launch until they were happy with the sound performance, I'm told.
Technics' head of headphone business, Kazunori Otsu, says that in the 60+ years of Technics' lifetime, "high quality music experiences" have progressed from in the home, with dedicated hi-fi separates, to almost anywhere in everyday life thanks to portable headphones.
He states that while the "way we listen to music has changed" over the years, "Technics' passion has not."
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