Building upon the success of the TH900mk2, the Fostex TH909 are premium reference open-back headphones well suited for professionals and audiophiles. The TH909 feature a remarkably designed driver unit with a 1.5 Tesla (15,000 gauss) magnetic flux density and bio-dynamic 50mm diaphragm. The detachable connectors use a rhodium plating finish, which offers high hardness with abrasion and corrosion resistance. The housing features a traditional Japanese lacquered Bordeaux finish, while the updated earpad design provides a low-resilience cushion to ensure a comfortable fit. The included unbalanced cable is made from 7N grade oxygen-free copper (OFC) with a gold-plated 1/4" TRS plug and can be replaced with optional cables such as a balanced cable with XLR connectors. Additionally, the headphones come with a stand and carrying bag. Wider dynamic range with low distortion Uses 1.5 Tesla 50mm driver with repulsion magnet Diaphragm Material: Proprietary "Biodyna" technology (bio-cellulose and inorganic fiber admixture) Provides rich low frequency, natural midrange, and remarkable presence in high-frequency reproduction Double-layer structure etching metal grilles are used as housing opening Housing cover uses Japan Lacquer Bordeaux finish manufactured by craftsmanship of "Sakamoto Urushi Factory" established in 1900 Custom-made 7N grade (99.99999%) high-purity OFC (Oxygen Free Copper) unbalanced cable (model ET-H3.0N7UB equivalent) is included as standard Equipped with detachable connector Supports balanced connection with optional XLR cable (model ET-H3.0N7BL) Detachable connection parts use rhodium plating finish offering high hardness with abrasion and corrosion resistance Updated earpad design adopts a low-resilience cushion to achieve a comfortable fit and the best audio performance Compatible with the optional cables made for the TH900mk2