dBV (upper case V)

Abbreviation for decibels as referenced to voltage. Similar to dBu, dBV specifies a relative voltage level without regard for impedance and is used to measure input and output levels for electronic audio equipment. The reference voltage level, however, is one volt. So one volt equals 0 dBV as opposed to the .775 volts for dBu. The formula for calculations is the same as for dBu: dBV = 20log (V2/V1). The dBV rating is most commonly found in consumer equipment that uses nominal operating levels of -10 dBV. It is simply a standard that was adopted many years ago. -10 dBV = .316 volts. You can prove that by checking it against the 1-volt reference. 20log (.316/1) = -10 dBV.