Ligyrophobia is a fear of loud sounds, especially sudden and unexpected ones. more...
For example, listening to a CD that starts with a minute of silence and then suddenly goes into loud rock music would be extremely startling for a person with ligyrophobia (assuming they had no prior knowledge of the content of the CD), as well as anyone most likely. The difference is that people with this phobia actively fear such an occurance.
They may be fearful of devices that can suddenly emit loud sound, like computer speakers or fire alarms. When operating a home theater system, computer, television, CD player, etc., they may wish to have the volume turned down all the way before doing anything that would cause the speakers to emit sound, so then once the command to produce sound is given, the user can raise the volume of the speakers to a comfortable listening level.
Another example is watching someone blow up a balloon beyond its normal capacity. This is often a somewhat unsettling, even disturbing thing to watch for a person with ligyrophobia, as the sufferer knows that a loud sound will soon result. Another common situation of ligyrophobia would be waiting for a bell to ring or a fire alarm to sound.
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