Psychoacoustics Exam 4 | 30 Questions with 100% Correct Answers | Updated & Verified

Define Equal Loudness Levels and How do we determine them? - ANS - By definition, when one refers to the loudness level of a sound, one is comparing the loudness of that sound with the loudness of a 1000 Hz tone. Loudness level is measured in units called phons. By definition, the loudness level of a sound in phons is equal to the dB SPL of a 1000 Hz tone judged equally loud. 20 phons is the loudness of a 1000 Hz tone at 20 dB SPL and the loudness of any other frequency sound that is perceived equally loud. A sound of 40 phons has the same loudness as 1000 Hz at 40 dB SPL. A sound that is 80 phons is as loud as 1000 Hz at 80 dB SPL, and so forth. An equal-loudness curve (contour) connects points of equal loudness across frequency. Fletcher-Munson curves Iso-loudness curve Phon curve Why do we use loudness scales as opposed to loudness levels? - ANS - Loudness level indicates equal loudness, but not how much louder one sound is compared to another sound. A loudness scale indicates the relative loudness of sounds. We are not only interested in the loudness of a particular sound, but also in how much louder one sound is than another. Define the following terms: Phon and Sone What is the difference between them? - ANS - The phon is the unit of loudness level