FDX – FIIO Japan,FDX – FIIO Japan,FiiO Announced New Flagship IEM's FiiO FD7 and FiiO FDX »,FiiO FD7/FDX] 12mm dynamic driver with its diaphragm using pure beryllium, with an outer-magnet field, up to 1.5 Tesla magnetic flux. | Page 74 | Headphone Reviews and Discussion - Head-Fi.org,FiiO Announced New Flagship IEM's FiiO FD7 and FiiO FDX »,