Convert Sabin (sabin) to Acre (US Survey) (ac (US)) instantly.
About these units
Sabin (sabin)
A sabin is the acoustic unit of sound absorption area, equivalent to the absorption provided by one square foot of a perfectly absorbing surface. Unlike geometric area units, the sabin measures how much sound energy a surface absorbs rather than its physical size alone. Materials with partial absorption effectiveness—such as acoustic tiles or drapes—contribute fractional sabins depending on their absorption coefficient. Architects and acoustic engineers use sabins to design theaters, concert halls, classrooms, and workplaces. The unit translates directly into reverberation time calculations, making it a foundational concept in architectural acoustics.
Acre (US Survey) (ac (US))
The US survey acre is based on the US survey foot, making it slightly different from the international acre. With a value of 43,560 survey-square feet, it appears extensively in historical property records and federal land surveys. Because millions of acres in the United States were mapped using PLSS, the survey acre remains necessary for interpreting legal land rights, even though modern mapping often uses metric units or the international foot. This specialized acre illustrates how subtle unit differences can survive for centuries due to legal and administrative inertia.