Decibels, Loudness

woodleywonderworks

From woodleywonderworks on flickr

When someone returns from a heavy metal concert they don’t usually comment loudly about how many Watts per meter squared they experienced.

Decibels might make sense.  People tend to know that 120 Decibels is a lot.

This system has been devised and units of decibels measure perceived loudness.

It increases on a logarithmic scale, so something that seems twice as loud really has 10 times the intensity.

Position also can vary the perception of sound such as when a noise emitter comes nearer to you the frequency seems greater and the pitch higher (Doppler Effect).