Noise-cancelling earbuds are electronic devices typically worn to listen to audio signals or music from a portable media player, though they can be used to listen to other devices as well. Unlike headphones, earbuds have two small earpieces that are placed just inside the entrance to the ear canal, rather than cups that go over the ears. How far these earpieces extend into the ear canal can have a tremendous impact on the amount of outside noise that can be heard. This is often called noise isolation. Noise-cancelling earbuds, on the other hand, have a system that actively works to cancel out any external noises that might also enter the ears of the wearer.
Many manufacturers in the audio industry produce different models of noise-cancelling earbuds, which can be quite expensive in comparison to more basic headphones. Earbuds, in general, are often preferred by people who find larger headphones to be too bulky, especially when worn during exercise or other physical activity. These devices typically have a single connection plug that is inserted into a media player, from which a cord extends that splits into two cords, each connecting to a separate earbud. This allows noise-cancelling earbuds to be more easily worn by someone who is moving, without the potential for slipping off that headphones often have.
Noise-cancelling earbuds have an internal computerized system that actively seeks to cancel out external sounds and noises that may enter the ears of the listener. This is in contrast to other earbuds and listening devices that may be labeled as “noise isolation” devices. Noise isolation is typically achieved by increasing how deeply into the ear canal the earbuds fit or extend when worn. This works to physically block out external sounds and is especially effective for ambient sounds such as the engines of an airplane or the sound of loud fans in powerful computers or servers.
These noise isolation methods do not work as well for sudden or intermittent sounds, such as people speaking, so noise-cancelling earbuds can be more effective for such purposes. Noise-cancelling earbuds typically use a system that includes a tiny microphone that picks up noises in the area around the listener. A microprocessor in the earbuds then processes these sounds, especially sudden sounds such as a person talking, and creates an inverse sound pattern that matches the original sound.
The noise-cancelling earbuds then play this sound for the wearer, in addition to the audio signal being listened to. The original sound and the inverse sound effectively cancel each other out, and neither sound is audibly perceived by the listener. Some earbuds include both noise-cancelling and noise isolation features, making just about all external sounds completely blocked.