The FiiO FDX is an advanced set of in-ear monitors designed for audio enthusiasts who demand high fidelity sound reproduction. These monitors are equipped with a hybrid driver configuration that combines balanced armature and dynamic drivers, allowing for a well-rounded audio performance across various frequencies. The FDX is crafted with attention to detail, including a high-quality build that incorporates premium materials for durability and comfort during extended listening sessions. The design focuses on ergonomics to ensure a snug fit while providing excellent sound isolation. Users can expect deep bass response, clear mids, and crisp highs, making them suitable for a wide range of music genres. Additionally, the FiiO FDX features a detachable cable system for easy upgrades and replacements. Specifications may include an impedance of around 16-32 ohms, sensitivity ratings up to 111 dB/mW, and a frequency response range between 20 Hz to 40 kHz, catering to both casual listeners and audiophiles alike.