# Decibel and Power Converter

### What's a dB?

Decibels (dB) can be described as a ratio of power between two signals. It
is useful for comparing signals where the difference between them is too small
to be viewed linearlly/directly. The name Bel is in reference to Alexander Graham Bell.
Originall, the unit used was just plain old Bels, but it was found that it is more
common to have resulting values smaller than a single Bel, e.g. one tenth Bel. Thus,
it became standard to use decibels instead, where one decibel is one tenth of a single
Bel. A value/power ratio is converted to Decibels by the formula dB = 10*log_{10}(ratio),
e.g. if power A is 2.0 and power B is 1.0, their ratio is 2.0/1.0, and the
result decibel is 10*log_{10}(2/1) = 10*log_{10}(2)