Which headphones should I use?
Ear bud headphones
These are in common use because they are relatively cheap and are often included in the purchase price of a personal music player. They are positioned at the entrance to the ear canal but, because the fit is quite loose, sound tends to leak to the outside world. Conversely, sounds from the outside can often be heard relatively easily.
To hear the music clearly it can be tempting to turn up the volume when using ear bud headphones. However, there is a risk that volumes may reach dangerously loud levels which can potentially damage hearing.
Sound isolating earphones
Sound isolating earphones also fit into the entrance of the ear canal, but are able to block outside noise and more effectively channel sounds from the player into the ear. This is achieved using a rubberised sleeve around the earphone tip which, once placed in the ear, acts as a seal. It is known as a ‘passive’ method because no electronic manipulation of sound is involved.
Various models are available and they look somewhat like ear bud headphones being similarly small and lightweight. It is important not to turn the volume up too loud as the sound source is very close to the eardrum. With sound isolating earphones, outside sounds are blocked out and so their use in certain situations is potentially dangerous.
Noise cancelling headphones
Noise cancelling headphones have cushioned muffs or cups that rest over the ears and have the appearance of traditional headphones.
Using clever electronics, they are able to reverse the ambient noise from outside and cancel it out. They work best where the background noise is constant and low frequency, as on a train or plane, and the degree to which they reduce noise pollution depends on the model purchased.
Because of the ‘active’ electronics, noise cancelling headphones require batteries to power them. The audio signal from the music player also undergoes some electronic processing and this can slightly distort the sound being listened to.
However, music can be enjoyed at lower volumes and so noise cancelling headphones are potentially safer for the hearing system. As with other headphone types, being mindful of personal safety is important when reducing outside sound.
Open- and closed-back headphones
Traditional headphone styles vary in that they can be open or closed at the back and the ear pad can either rest on or cup the ears. These variations create different listening conditions.
To block out background noise effectively, closed back headphones work best where the ear pad completely cups the ears. The ear cup fit is usually quite tight to stop unwanted sound getting in and to prevent leakage of the audio sound to the outside. Under these conditions, music can be listened to at lower volumes.
Where the ear pad is smaller and lightly rests on the ear, more sound can leak in and out and it can be tempting to turn the volume up higher.
The real connoisseur may prefer open back headphones because they offer the most natural sound reproduction. However, they are best suited to quiet listening conditions to avoid the problem of sound leaking out.