CompTIA DHTI+ Practice Questions

Answer - B - The amplifier’s output should be increased by three to have a 100 dB increase in speaker output.

Key Takeaway: Decibel, or dB, is a logarithmic unit of measurement that expresses the magnitude of a physical quantity relative to a specified or implied reference level. It is a dimensionless unit and uses base-10 logarithms. A change in the ratio by a factor of 10 is a 10 dB change. A change in power ratio by a factor of 100 is approximately a 100 dB change which relates to tripling the quantity.