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

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

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 - sengpielaudio

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

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 = two times the voltage
+12 dB = four rimes the voltage
+20 dB = ten times the voltage
+40 dB = hundred times the voltage

Not often one is interested in power, if we consider audio engineering.
Do not ask what the power amplification is.
Leave that to the telephone company.
Is there really a power amplification?
Read the text at the bottom.

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

+3 dB = two times 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

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.

Enter a value in the left or right box.
The calculator works in both directions of the ↔ sign.

The voltage is always given as RMS value - but not the electric power.

There is also the reference power P₀ = 1 milliwatt or 0,001 watt ≡ 0 dB_m

Amplification and Damping

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

Level in psycho acoustics as subjectivly perceived loudness (volume)

Amplifier conversion - Convert decibels to voltage gain / loss

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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Voltage V: volts	↔	Voltage level L_U: dBV
$V = V_0 \cdot 10^\frac{L_V}{20} \ \mbox{volts}$		$L_V = 20\, \log_{10}\left(\frac{V}{V_0}\right) \ \mbox{dBV}$
Reference voltage V₀ = 1 Volt ≡ 0 dBV

Voltage V (Audio): volts	↔	Voltage level L_U (Audio) : dBu
$V = V_0 \cdot 10^\frac{L_V}{20} \ \mbox{volts}$		$L_V = 20\, \log_{10}\left(\frac{V}{V_0}\right) \ \mbox{dBu}$
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 (telephone) P: watts	↔	Electric Power level (phone) L_P dB_m

Reference power P₀ = 1 milliwatt (mW) = 0.001 W ≡ 0 dB_m

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

Voltage gain v = 1 ≡ 0 dB

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

gain factor v = P₂/P₁: for energy quantities, e.g. power	↔	amplification level L: power level dB

Power gain v = 1 ≡ 0 dB