Loudness vs Pitch
Loudness and Pitch are characteristics of sounds. Loudness refers to the sound level, and the pitch is related to the frequency of the sound. These are often parts of music and sound engineering vernacular as well as in physics because some of the concepts in music are directly explained by these terms. Nevertheless this article focuses on the physics of the loudness and the pitch.
Loudness
Loudness is a subjective quantity of the sound. It is the physical perception of the intensity of sound. However, the relationship between loudness and sound intensity is complex and, therefore, often confusing.
Loudness is affected by frequency too because the human ear perceives sound intensities at different frequencies differently. Duration is also a factor of loudness. Human ear perceives long bursts of sound louder than the short bursts of sounds. This is due to the nature of the hearing mechanism of the ear. Loudness increases for the first .2 seconds and then stays unchanged until the source stops.
Relative loudness is generally measured based on the assumption of proportionality to the logarithm of sound intensity; i.e. the sound intensity level. Unit of measurement of Loudness is sone, and for the loudness level, it is phon.
Pitch
The pitch is the perception of the highness or the lowness of the sound. It is strongly related to the frequency of the sound, but not exclusively. Loudness also affects the pitch. Up to 1000 Hz (1 kHz), the increment in loudness decreases the pitch, and in the range of 1000-3000 Hz (1-3 kHz) the loudness has no effect on the pitch. Beyond 3000 Hz (3 kHz) the increase in the loudness causes and increment in the pitch. Pitch is measured in mels.
What is the difference between Pitch and Loudness?
• Basically, pitch is the lowness or the highness of the sound which is determined by the frequency of the noise. Loudness also affects the pitch but only as a secondary factor.
• Loudness is the measure of the intensity of the sound for an observer. It is directly related to the sound intensity.
• Loudness is measured in sones and loudness level, in phons, whereas the pitch is measured by mels.
• In music, high pitched noises are penetrating sharp while low pitch noises are heavy and smooth. High pitch noises are used to invoke excitement fear and thrill.