Sound Pressure Level

Sound Pressure Level

NO-07
ASPCSPAdvanced

Formula
Lp = 20 × log₁₀(p/po)
When to Use

Convert measured sound pressure to decibels relative to the threshold of hearing.

Symbol Legend
SymbolMeaningUnitNote
LpSound pressure leveldB
pMeasured sound pressureN/m²
poReference sound pressurethreshold of hearingFixed reference

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