digital music players cause hearing damage
The cool and compact MP3 and CD players may easily cause tinnitus or noise induced hearing loss. Yet, few are aware that these popular entertainment devices can be extremely hazardous to their hearing.
The players are capable of delivering high sound levels for hours on a single battery charge. The user risks exposing his or her ears to highly excessive dB levels hour after hour.
The devices are commonly used when people are on the go to and from school or work, for example. In noisy traffic the volume is often turned up to drown out the outside noises. When the traffic noise levels are 85 dB the personal stereo volumes are easily turned up to levels damaging to the ears. As a general rule, you should never expose your ears to noise levels of 91 dB for more than two hours in one day.
Personal stereo noise levels at 91-139 dB
Boston University researchers tested six different commercially available portable CD players. The researchers found that that the players delivered sound levels between 91 and 121 dB out-of-the-box. When other earphones than those provided with the players were used, the sound levels reached as high as 139 dB - about the noise level of a jet airplane on take-off.
As a result, caution should be exercised when using MP3 or CD players. The researchers recommend that listening to portable stereos be limited to one hour or less per day at levels about 60 percent of the maximum volume levels of the player. They warn that the smaller the headphone, the higher the sound level for a given volume control setting.
Some personal stereos come with a limiter setting preventing sound levels above 100 dB but some people still choose to switch the limiter off. This may have dire consequences for their hearing.
Sources: "Output levels of commercially available portable compact disc players and the potential risk to hearing", Ear and Hearing, December 2004, Vol. 25 No. 6. "Digital music craze stores up ear trouble for iPod fanatics", Scotland on Sunday, 8 May 2005.
Summary provided by www.hear-it.org.