Final is a respected Japanese manufacturer of premium-quality headphones, earphones, and other audio products. Founded in 1974 by the late, great audio legend Kanemori Takai, Final Audio Design (as the company was first known) was from the beginning a company known for a technology-rich but always music-centred approach to product design. In 2015, about a year after Takai-san’s passing, the company simplified its name to Final and today is led by Mitsuru Hosoo, the firm’s visionary President and chief of product design. Hosoo-san is keenly aware of Final’s ‘music first’ heritage and under his guidance the firm has launched an expanded range of SONOROUS-series dynamic-driver headphones as well as several important new families of affordable high-performance earphones. But at the Axpona 2017 and Munich High-End 2017 events, Final previewed what is arguably its most ambitious new product to date: namely, the revolutionary D8000 planar magnetic headphone that is the subject of this review.
In a way, Final’s planar magnetic D8000 came as a great surprise, given that the firm enjoyed such a strong reputation for building ultra-high-performance dynamic driver-based products (a good example would be the famous SONOROUS X headphone). However, through a series of seminar-type presentations on the D8000, Final made it clear that its aim was to create a breakthrough, ‘best of two worlds’ design that would, in Final’s terms, offer, “...the sensitive high ranges of planar magnetic models and the volume and open-feel bass tones of dynamic models.” With this objective in mind, Final took a ‘clean-sheet-of-paper’ design approach for the D8000 and in the process effectively wound up reinventing planar magnetic driver technology, as we know it.
From the start, Final was aware that planar magnetic drivers offer certain inherent benefits such as light, fast, and responsive membrane-like driver diaphragms that, unlike dynamic driver cones or domes, enjoy the advantage of being driven over their entire surface area and not just from a centrally positioned voice coil. However, planar magnetic drivers also pose certain design challenges that are not easily overcome such as potential membrane resonance problems and distortions caused by airflow turbulence as sound waves pass through the grid-like magnet arrays used in most planar magnetic designs.
After weighing these advantages and potential drawbacks, the Final team came up with what may well be a different and better kind of planar magnetic driver. First, they elected to use an essentially ring-shaped driver diaphragm featuring an inward-spiraling circular band of aluminium voice coil traces. In the Final design, these traces are not bonded to the diaphragm membrane via an adhesive (as in many other many planar magnetic designs), but rather are etched into the surface of an ultra-thin film diaphragm material with an extremely thin aluminium outer coating. This etching process, says Final, yields a diaphragm/voice coil assembly fully one third lighter than equivalent dynamic driver assemblies of the same diameter. The diaphragm also uses a series of concentric ring-like corrugations that help promote more linear motion over the diaphragm’s entire working surface. By dispensing with the usual voice-coil adhesives and using a corrugated diaphragm, the D8000 driver is said to achieve superior “reproduction of subtle high frequencies.”