Page 5: Pitch And Loudness
image taken from source #6, http://www.explorations.org/everdaysci01_fall98_pitch.html
Pitch allows us to compare one sound with another sound. Pitch is determined by the sound's frequency. Frequency is the number of vibrations per second. Pitches for musical notes have been standardized so that all the instruments use the same pitch. Our present standard of pitch is a' = 440 vibrations (cycles) per second.
image taken from source #1, page 46
Pitch acuity is when we are able to distinguish differences in pitch. Pitch acuity can sometimes be confused with loudness. Changes in loudness are sometimes percieved as changes in pitch.
image taken from source #1, page 49
Loudness is the way that we measure the intensity of sound. We percieve loudness from the amplitude of the sound wave. Loudness is measured in a unit called the phon. The intensity is measured in a unit called the decibel. Phons and decibels are only the same at a pitch of 1000Hz. At any other pitch, the phons and decibels have to be measured.
Other Pages:
Page 7:The Way We Perceive Sounds