Zyra's site //// CONCEPTS //// SCIENCE //// SITE INDEX
Decibels are commonly believed to be just a measurement of how loud a sound is. But there's more to it than that, because they are convenient way of dealing with scientific phenomena that worth logarithmically. Things like signal-to-noise ratio for example. Logarithms - classic oldfashioned conjuring trick for doing hard sums like magic (link here to see how the conjuring trick is done), are also a way in which some things in nature work, like sound for example.
deciBels (dB) in sound:
Approximate descriptions of levels of sound
|0 dB||Threshold of hearing|
|10 dB||Rustling of leaves|
|30 dB||Quiet conversation|
|40 dB||Average home|
|50 dB||Normal conversation|
|60 dB||Busy shop|
|70 dB||City street|
|80 dB||Busy workplace|
|90 dB||Underground railway|
|100 dB||Pneumatic drill 10ft away|
|110 dB||Propeller aircraft taking off|
|120 dB||Jet aircraft taking off|
What's interesting here is that each 10dB added makes the sound TEN TIMES as loud. So, 90dB is quite loud, but 100dB is ten times louder, and 110dB is 100 times louder, etc.
What's really good about this is that it's possible to put things on a scale which is understandable even though the ratios between them are very large.
If you found this page useful, see [response]