I purchased these this summer, but I also own other earphones and headphones, so the usage time is short. Product Description: Sound quality designed to focus on "voice" - Equipped with a 40mm dynamic driver, the acoustic characteristics of the internal acoustic space have been thoroughly pursued. Through the results of final's unique acoustic research, we have achieved a sound quality design that focuses on "voice." It reproduces even the subtle nuances of the vocals, as if the artist is singing right next to your ear. Furthermore, it is equipped with a unique algorithm ANC that prioritizes sound quality. The vocals and the tones of each instrument stand out clearly in the well-insulated silence, each spreading clearly.