Radius as a company is probably not widely known among audiophiles, unless if you are based or have visited Japan, chance are, you won’t find their products in stores near you. Their history actually started in United States on May 1986 as a subsidiary of Apple. In 1991, the company expanded to Japan. Not long after that, in 1996, the Japanese branch became independent and separated from their United States origin. Since then, the Japanese Radius has been focused on making peripheral for Apple devices and also on home and portable audio market. The United States branch however, changed their name to Digital Origin, allowing the Japanese company to keep the Radius name today. Quite a journey, eh?
The current product lines of Radius consisted of home and portable DAC and amplifier, earphones, the digital audio player software called NePLAYER and some other accessories for Apple and Android devices. What I’m interested in is their audio product of course, in the case of IEM, Radius has covered the market from the bottom into the mid-fi range.
Their highest-end IEM is unique that they have Dual Diaphragm Matrix (DDM) driver, possibly the first that combine dynamic and piezoelectric driver in each side of the IEM. That current lineup consisted of two identical siblings, TWF31 and TWF41. I have used their flagship, TWF41 for a couple of months now, while it’s not trying to compete with the (ridiculous) high-end market for IEM, it’s a quite impressive performer in their price range… and unique.