Flagship-level DLC diamond diaphragm, for an amazing, powerful sound]: The FD3 Pro headphones benefits from the numerous advantages of FiiO's new dynamic driver. The diaphragm is made of Diamond Like Carbon (DLC) which is both impressively rigid and helps to reduce unneeded distortion yet also surprisingly light, allowing the driver to have excellent transient response. The result is a driver with excellent sound quality and minimal distortion with the added bonus of being ultra-sensitive. Flagship-grade acoustic prism, take your breath away. The acoustic prism so effectively used in the flagship FD5 for great sound quality is also featured in the FD3. Like with the FD5, the acoustic prism system brings numerous benefits such as eliminating high frequency standing waves, enhancing overall sound wave diffusion, and even effectively solving the problem of time delay caused by sound wave propagation path in the cavity. This all leads to marvelous sound quality. Better sound with semi-open design, makes you less tiring and the sound less forced. The semi-open design of the FD3 based on FiiO's patented technology for balanced air pressure within brings several advantages. Not only does such a design led to more natural sound, but it also effectively protects your hearing by balancing air pressure within the FD3 leading to less pressure on your eardrums. 2.5D film coating glass faceplate the unique celluloid panel is covered with 2.5D film coating glass for a pure yet fresh transparent look. And the aluminum-magnesium alloy of the body makes the FD3 exceptionally light, making it easier and more pleasurable to carry around. And the aluminum-magnesium alloy main body is made in an industrial process combining five-axis CNC processing and hand polishing. Well-equipped just for you The FD3 Pro comes with an exclusive cable made of high-purity monocrystalline silver-plated copper, with 8 strands of 19 wires each for a total of 152 wires braided together in Litz Type 2 style. In addition, the cable features left blue and right red markings for convenience as well as interchange audio plugs, allowing you to freely switch between 2.5/3.5/4.4mm plugs depending on your source. With this cable, every music note has never been clearer!