Closed-back headphones were mostly used by the military and radio/telephone operators prior to 1937. Beyerdynamic launched the DT 48 headphones, the first consumer-grade headphones, to fill a niche in the industry. They became very successful, but they were unable to play audio in stereo. By 1958, the Koss SP/3 stereo headphones, the first modern closed-back model, had taken the world by storm.
Closed-back headphones are constructed precisely as their name implies. Closed-back headphones have sealed housing that prevents sound from leaking. Outside noise is also muffled by this, resulting in remarkable isolation. You’ll note that these headphones are a little heavier and chunkier than open-back headphones.
Closed-back headphones are common because they block out the outside noise and allow the music to shine. You’ll see a small increase in bass response as well as some passive isolation. Closed-back headphones have passive noise cancellation, making you sound as if you’re in the studio with the people you’re listening to.
This success trait is ideal for situations requiring a high level of attention and concentration. Closed-back headphones are still the preferred choice for studio use. They allow you to track silent instruments or voices without having to think about your mic picking up the sound from your headphones.