How loud is sound?

Answer 1

Sound is as loud as a piece of string is long - swapping the SI units from m to dB of course.

add. Approximately one-half of the population can hear sounds below 0dB. (Assuming no damage.) Ordinary speech at 1.5m is perhaps 75dB, and loud speech at the same distance perhaps 85 - 90 db. To preserve your hearing, you should use hearing protection above these levels.

The loudest sounds we should hear are about 120dB. Sounds above 130dB may cause instant damage. Above 140dB will be felt as pain.