Unparalleled precision from cutting-edge The FA1 is created with advanced industrial-grade 3D printers. Compared to traditional moulding or injection moulding processes, 3D printing in conjunction with sophisticated digital modelling allows us to archive greater consistency and better overall sound. Customized Knowles driver for mesmerizing sound, every time Inside the FA1 is a specially-customized balanced armature driver co-developed by FiiO and Knowles that especially capitalizes on the strengths of BA drivers for excellent sound. And with its low 15-ohm impendence you can be sure the FA1 will sound good out of anything, even from your phone! Precise balanced armature driver The balanced armature drivers in the FA1, in conjunction with the specially designed micrometer sound tube, have been tuned to provide natural yet smooth-sounding frequency response, free from any dips or peaks. With the FA1, you will get robust yet quick bass, wonderfully rich mids, and treble featuring detail and speed that only balanced armature drivers can provide. Honed by thousands of ears The shape of the FA1 was designed from the input of tens of thousands human ear shapes, to ensure maximum comfort and that the sound flows unimpeded to your ears. Choosing the perfect outer shell The outer shell of the FA1 employs a skin-friendly resin material, specially chosen for maximum wearing comfort and for its ability to durably retain its colour and lustre for years to come. Light as a feather Thanks to advanced 3D printing technology and the skin-friendly resin material of the shell, a single FA1 ear unit weighs in at a mere 4.5g for unparalleled wearing comfort. Detachable cables for unleashed Not only does the included MMCX cable enhance the durability of the FA1 by making it easy to replace, it also enhances the sound you get. The included 3.5m-terminated cable is made of oxygen-free copper-plated silver wire for supreme clarity and vast soundstage.