About Decibel Calculations

Decibels (dB) are a logarithmic unit used to express the ratio of two values of a physical quantity, often power or intensity. They are widely used in various fields including acoustics, electronics, and telecommunications.

Key Formulas

1. Power Ratio to dB:

\[dB = 10 \log_{10}\left(\frac{P_1}{P_2}\right)\]

2. Voltage Ratio to dB:

\[dB = 20 \log_{10}\left(\frac{V_1}{V_2}\right)\]

3. Sound Intensity Level:

\[L_I = 10 \log_{10}\left(\frac{I}{I_0}\right)\] where \(I_0\) is the reference intensity, typically \(10^{-12}\) W/m².

4. Sound Pressure Level:

\[L_p = 20 \log_{10}\left(\frac{p}{p_0}\right)\] where \(p_0\) is the reference pressure, typically 20 µPa in air.