logarithmic ratio quantity · International · Modern

bel

exact

Definition

1 bel = 10 decibels. For a power-like ratio, 1 B corresponds to a ratio of 10:1.

bel converts through a formula rather than a simple multiplier.

The bel is named for Alexander Graham Bell; acoustics and telecommunications overwhelmingly use its tenth, the decibel.

Modern use is context-dependent and varies by region or measurement system.

Source tier — · confidence high

logarithmic ratio quantity · International / acoustics / signals · Modern

The decibel is one tenth of a bel and expresses a base-10 logarithmic ratio. It is not inherently a unit of sound pressure.

logarithmic ratio quantity · SI-compatible / electrotechnology / acoustics · Modern

The neper expresses logarithmic ratios using natural logarithms rather than base-10 logarithms.