Lifestyle Asia Hong Kong. At just 38 grams, the Sony MDR-3 switches the 3.5mm jack in favor of digital plug-and-play connectivity with direct USB-C. Sony has launched the MDR-3R wired USB-C headphones, reviving the design of its original 1979 Walkman headphones with updated drivers, an in-line remote and built-in. 5, 2026, launched the Sony MDR-3R, a USB-C remake of the open-ear headphones that shipped with the original Walkman in 1979.