pressure
decibels
general definition of decibels
Application to amplifiers and filters gains
Application in acoustics
Sound Pressure Level (\mathrm{dB}_{SPL} or \mathrm{dB}_{ref=20 \mu Pa})
L = 20 \ \mathrm{log} \left(\frac{P_{rms}}{P_o}\right) with P_o=2.10^{-5} \ \mathrm{ Pa}