Closed-back headphones seal the back of the driver housing to keep the music from being heard by bystanders and to isolate the listener from the outside world. In high-end headphones, closed-back is sometimes a compromise in sound quality compared to open-back models. But if you need to keep your music to yourself and block outside noise, there’s no better choice than a headphone like the Focal Stellia or Sennheiser HD820. Pair them with a headphone amplifier like our Gilmore Lite mk2 or GS-X mini for the ultimate experience.