DECIBEL (dB) CONVERTER

Decibel (dB) converter for dB to magnitude conversion and multiplication of dB by a number. Formulas for decibel to field and power ratio conversions and multiplication of decibel by a number are given below.

The power relationship in dB	power ratio in dB = 10log₁₀ P/P₀
The field relationship in dB	field ratio in dB = 20log₁₀ A/A₀
Multiplication by a number n for power relationship	L_A (dB) = L_B(dB)+10log₁₀n
Multiplication by a number n for field relationship	L_A (dB) = L_B(dB)+20log₁₀n

If P is greater than P₀ then ratio is positive; if P is less than P₀ then ratio is negative.

P is the measured power and P0 is the reference power.

A is the measured amplitude and A0 is the reference amplitude.

dB - Ratio conversion
Magnitude type	Power	Field
Conversion type	dB to ratio	ratio to dB

Ratio (factor)		Decibel
Enter a number!		Enter a number!

Multiplication by a number (n * B(dB) = A(dB))
Magnitude Type		n	B (dB)	A (dB)
Power	Field
	Enter a number!		Enter a number!

Note: Use dot "." as decimal separator.

Definitions:

Decibel (dB): Decibel is a unit used to express relative difference in power or intensity, usually between two acoustic or electric signals, equal to ten times the common logarithm of the ratio of the two levels.

Examples to power quantities: Sound power measurements, power spectral density random vibration.

Examples to field quantities: Voltage, displacement, velocity, acceleration, force, sound pressure, strain.

Reference acoustic sound pressure level dB(SPL) : The lowest sound pressure which is usually considered the threshold of human hearing (at 1 kHz) is approximately 2*10^-5Pa .

Supplements:

Vibration Calculators