dB calculate - dB decibel calculation voltage power ratio sound pressure level matching dBA SPL sound pressure intensity ratios

dB decibel calculate calculation calculator computation calculate calculation convert conversion factor ratio voltage power reference value level acoustic velocity sound distance electrical resistance voltage power ratio sound pressure level matching dBA dB SPL sound pressure intensity ratios energy loudness sound energy density audio reference field energy quantity quantities field energy quantity value magnitude table tables chart charts sound studio techniques acoustics volts volt watts watt sound pressure intensity sengpielaudio Sengpiel Berlin

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How to calculate dB?

• The decibel calculator (dB) - a valuable tool •

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With "dB" and "ratio" near the input boxes, you decide what is calculated and which box is the input.
With "field quantity " and "energy quantity " you decide if it is
20 times (field quantity, e.g. volts) or 10 times (energy quantity, e.g. watts) in the formula.

Enter a value in the left or right box, then press the TAB bar or make
a mouse click at an empty space at the side, to get the solution.
The calculator works in both directions of the ↔ sign.

Voltage Ratio and Voltage Level - sengpielaudio

Power Ratio and Power Level - sengpielaudio

Level of field quantities

Level of energy quantities

Sound pressure, sound intensity, and their levels:
Conversion: dBu in volts, dBV in volts, volts in dBu and dBV

Sound Field Quantities :-)
sound pressure, sound velocity, particle displacement, sound distance, voltage, current, electric resistance.
Inverse Distance Law 1/r

Sound Energy Quantities
Sound intensity, sound power, sound energy density, electric power.

Inverse Square Law 1/r²

a₁ and b₁ is the reference
'a' could be a voltage V and 'b' could be a power P. P ~ V²

Sound pressure
Sound field size

Sound pressure level

Reference sound pressure p₀ = 20 μPa = 2 × 10^-5 Pa (0 dB)
Field quantities, as the sound pressure, will always be shown as effective value (RMS).

Sound intensity
Sound energy size

Sound intensity Level

Reference sound intensity I₀ = 1 × 10^-12 W/m² (0 dB)
dB-Scale for linear field quantities, like volts and sound pressures dB-Ratio - sengpielaudio

ratio

There is no decibel conversion from dBA to dBSPL or vice versa.

Charts: Conversion of voltage or power ratios to decibels dB

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Voltage V (audio): Volt	↔	Voltage level L_U: 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)

Voltage V: Volt	↔	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)

Electric power P: Watt	↔	Electric Power level L_P dB

Reference power P₀ = 1 W (0 dB)