Features of individual sounds

The main features determined by the auditory cortex are:


Pitch is the dominant frequency that we sense in a sound.


Loudness is related to the intensity of the vibrations making up the sound.


Timbre is a multidimensional feature that includes spectrum (the mix of harmonics that make up the sound), and the temporal changes of amplitude and spectrum over the life of a sound. Timbre is broadly defined as the sum of features that differentiate different sounds played at the same pitch and volume.


The difference in the amount of a sound heard in one ear relative to the other gives us a sense of the location of the sound from left to right. Other factors related to the way that sound is modified as it enters the ear from behind, above, in front, and below add to our sense of the location of a sound.


How long a single sound continues in time.

Features of Sound Groups


Harmony is a sense of relative consonant or dissonant relationships between multiple simultaneous sounds. This character is related to the relative simplicity or complexity of the mathematical relationship between frequencies.


Melody has to do with the character of a sequence of pitches over time. The order of pitches in time and their relative harmonic relationships to each other define the character of the melody.


Rhythm has to do with the pattern of individual sound events across time without reference to any pitch information


Tempo is our sense of an underlying base rhythm underneath the more complex features of rhythm.

Our sense of music, our understanding of speech and our ability to make sense out of environmental sound emerges from our ability to integrate these features into internal representations of phenomena.

Additional features like counterpoint, which has to do with harmonic interplay between independent melodic lines, are higher level relationships between sound groups, and would appear to be more cognitive that perceptual.