Sound unit

• dB, decibel - noise of sound measurement is called decibels. Ratio of the sound pressure to reference pressure to something.
• sone - a unit of perceived loudness equal to the loudness of a 1000-hertz tone at 40 dB above threshold, starting with 1 sone.
• phon - a unit of subjective loudness.
• Hz, hertz = unit of sound frequency is called hertz