Kanemori Takai, who founded final in 1974, tuned his products by ear. Vlad Savov of The Verge wrote that in an era of measurements and target curves, Takai "shrugged off modern methods to tune everything with his own ear." That habit still shapes the company. It voices the E series earphones from acoustic engineering and research into how people hear, and it judges the A series by how cleanly a driver starts and stops a sound. Its best-known engineering is in the D series headphones, which use a planar magnetic driver, a thin film held between magnets so its whole surface moves at once. final says the film in a conventional planar can hit the magnets in deep bass, so designers seal the earpads tightly to make up for it. final cushions the film with a layer of air instead, the company says, which lets the D8000 use breathable pads. The Headphone Show called the D8000 Pro's low end "probably the best bass that I've ever heard in a headphone." The brand suits listeners who prize natural timbre and space.

The E series is the usual way in. Every model uses a single small dynamic driver, and the E3000 is easy to drive from a phone. Everydaylistening found the E series has "stood the test of time." If you move up to the E5000, give it a little more power, since Headfonics found it sounded fuller and more dynamic from a medium-powered amp. Among the headphones, the D8000 Pro rewards a good amplifier. WaveTheory moved from his Violectric V281's single-ended output to its balanced one and heard more rumble, punch and control, and he concluded that "the bass wakes up a lot more when you give it a little bit more power." The D7000 needs even more drive. Tom Martin of The Absolute Sound ran it from a powerful dCS Lina amp, heard it as warm with weighty bass, and called it "a fun headphone that lets you get into the music." Almost every part of the D8000 is designed to come apart for repair and later upgrades.

final began in 1974 with a phono cartridge. Its first real product, designed by Yoshihisa Mori, had a figure-eight air-core coil and a cantilever cut from a one-carat diamond, and the company went on to build amplifiers and speakers and sell whole systems directly to listeners. Earphones under the final audio design name followed in 2009 and the first final headphones in 2013. Since 2011 the company has held earphone assembly sessions, where visitors try building a pair, at the Japan Audio Society's show and in Yodobashi Camera stores. In 2015 it moved its head office to Kawasaki, where it makes its own drivers, designs the jigs that build them, and assembles the D8000 by hand. Headfonics notes that the D8000's arched headband takes its cue from Yamaha's HP-1 and HP-2 of the 1970s. Tom Martin places final in the artisanal part of the market, which he says Japanese audio companies tend to excel at. The company says it wants people to keep its earphones the way they keep a mechanical wristwatch, the kind that becomes an antique.