dB calculator for amplification gain and damping (loss) factor of an audio amplifier calculation decibel dB ratio

● Calculation: amplification (gain) as factor ( ratio) ●
and damping (loss) as level in decibels (dB)

The amplification factor, also called gain, is the extent to which a device boosts the strength of a signal.
The damping factor, also called loss, is the extent to which a device reduces the strength of a signal.

Enter two values and press the right calculate bar in the line of the missing answer

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In analog audio engineering we deal only with 'voltage' amplification (gain) and damping (loss).
gain and loss

V₁ = V_in and V₂ = V_out.
V₂ > V₁ or V_out > V_in means amplification. The dB value is positive. (+)
V₂ < V₁ or V_out < V_in means damping. The dB value is negative. (−)
V₂ / V₁ or V_out / V_in means the ratio. The amplification or the damping in dB is:
L = 20 × log (voltage ratio V₂ / V₁) in dB. V₁ = V_in is the reference.

In physics, attenuation is regarded as a positive value.
This naturally leads to sign errors when entering numbers.

3 dB ≡	1.414 times the voltage	(−)3 dB ≡	damping to the value 0.707
6 dB ≡	2 times the voltage	(−)6 dB ≡	damping to the value 0.5
10 dB ≡	3.162 times the voltage	(−)10 dB ≡	damping to the value 0.316
20 dB ≡	10 times the voltage	(−)20 dB ≡	damping to the value 0.1

Using voltage we get: Level in dB: L = 20 × log (voltage ratio)

+6 dB = twice the voltage
+12 dB = four times the voltage
+20 dB = ten times the voltage
+40 dB = hundred times the voltage

If we consider audio engineering, we are usually not interested in power.
Do not ask what the power amplification is.
Leave that to the telephone companies or the transmitting aerials (antennas).
Power gain is really not used in audio engineering.
We got no power (energy) amplification.
Read the text at the bottom.

3 dB ≡	2 times the power	(−3) dB ≡	damping to the value 0.5
6 dB ≡	4 times the power	(−6) dB ≡	damping to the value 0.25
10 dB ≡	10 times the power	(−10) dB ≡	damping to the value 0.1
20 dB ≡	100 times the power	(−20) dB ≡	damping to the value 0.01

Using power we get: Level in dB: L = 10 × log (power ratio)

+3 dB = twice the power
+6 dB = four times the power
+10 dB = ten times the power
+20 dB = hundred times the power

If you search for the amplification ratio, given the dB value,
then go to the program dB calculation

Amplification (Gain) and Damping (Loss)

In audio technique the following "power or energy amplification " is rather unusual.

Voltage/Pressure amplification ratio	1	1.414 = √2	2	3.16 = √10	4	10	20	40	100	1000
Increasing of x dB	0	3	6	10	12	20	26	32	40	60

Power/Intensity amplification ratio	1	1.414 = √2	2	3.16 = √10	4	10	20	40	100	1000
Increasing of y dB	0	1.5	3	5	6	10	13	16	20	30

At the cut-off frequency f_c the dropped voltage is always fallen to the value of
1/√2 and the voltage level L is damped to 20 × log (1/√2) = (−)3,0103 dB.

Simply enter the value to the left or the right side.
The calculator works in both directions of the ↔ sign.

The voltage is always given as RMS value - but that is not valid for electric power.

There is also the reference power P₀ = 1 milliwatt or 0.001 watt ≡ 0 dB_m

Level in psycho acoustics as subjectivly perceived loudness (volume)
The vague human feeling of the double loudness (volume) is specified
with about 6 to 10 dB. This personal feeling is not an exactly measurable value.

Conversion Factor, Ratio, or Gain to a Level Value (Decibels dB)
Amplifier conversion − Convert decibels to voltage gain / loss
Calculator Voltage Gain − Voltage Loss and Power Gain − Power Loss

Conversion: Gain G, Voltage ratio A_V, and Power ratio A_P

Voltage gain

in dB

Power gain

in dB

Voltage ratio Amplification Factor Power and Decibels

= amplification factor (voltage)

Power ratio Amplification Factor Power and Decibels

= amplification factor (power)

V₁ = V_in and V₂ = V_out.
V₂ > V₁ or V_out > V_in means amplification. The dB value is positive. (+)
V₂ < V₁ or V_out < V_in means damping. The dB value is negative. (−)
V₂ / V₁ or V_out / V_in means the ratio. The amplification or the damping in dB is: L = 20 × log (voltage ratio V₂ / V₁) in dB. V₁ = V_in is the reference.

The word "power amplifier" is a misnomer. Power is not really something that can be "amplified". Voltage and current can be amplified. The term "power amplifier" although technically incorrect has become understood to mean an amplifier that is intended to drive a load such as a loudspeaker.
We call the product of current and voltage gain just "power amplification".
The total energy within a closed system due to the conservation of energy is neither increased nor decreased.

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Gain ratio v = V₂/V₁: for field quantities, e.g. voltage	↔	Amplification level L: voltage level dB

Voltage gain v = 1 ≡ 0 dB

Gain ratio v = P₂/P₁: for energy quantities, e.g. power	↔	Amplification level L: power level dB

Power gain v = 1 ≡ 0 dB

Voltage V: volts	↔	Voltage level L_U: dBV

Reference voltage V₀ = 1 Volt ≡ 0 dBV

Voltage V (Audio): volts	↔	Voltage level L_U (Audio): dBu

Reference voltage V₀ = 0.7746 Volt ≡ 0 dBu

Electric power P: watts	↔	Electric power level L_P: dB

Reference electric power P₀ = 1 W ≡ 0 dB

Electric power P (Telephone): watts	↔	Electric power level L_P: dB_m

Reference electric power P₀ = 1 milliwatt = 0.001 watt ≡ 0 dB_m