Definition:Decibel/Definition 2

Definition

The decibel is a unit for comparing levels of intensity of sound.

It is equal to $10$ times the logarithm base $10$ of the ratio of the intensity of the sound with respect to the intensity of a reference sound (usually taken to be the lowest audible sound of the same frequency (Physics)).

Conversion Factors

\(\ds \)

\(\)

\(\ds 1\)

decibel

\(\ds \)

\(=\)

\(\ds \dfrac 1 {10}\)

bel

Symbol

The symbol for the decibel is $\mathrm {dB}$.

Also see

• Definition:Bel

Source of Name

This entry was named for Alexander Graham Bell.

Sources

• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): decibel: 2.
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): decibel: 2.