Closed reference headphone for control and monitoring applications. For years now, professional users all over the world have placed their trust in our classic range: DT 770/880/990 PRO. The studio reference headphone boasts extremely detailed resolution and very transparent sound. The DT 770 PRO is a closed studio headphone that boasts impressive sound volume. The level of musical detail revealed make these headphones ideal for monitoring purposes. Ultra-low bass sounds are defined and reproduced crisply.