Hearing is not the same as listening

Did you hear what I heard? You'll never know. Our experience of the music we listen to is shaped by extensive processing of the raw vibrations that enter our ears. That processing, by the auditive and cognitive centers of our brain, is itself strongly shaped by a long trail of experiences, expectations and culture. Plus another dozen or more factors.

Most people are not so much interested in the mechanisms (both physically and mentally) behind listening. But listening is really where it all comes together. The enjoyment of music, the interpretation of performances, the judgment of audio reproduction quality is not done with our ears. It is done within our brain. The ears are the sensors that provide our brains with just a physical sample of the air vibrations that represent the sound. What those vibration mean, what they signify, and their ‘quality’ is determined by the brain.

In his latest book "I am a strange loop", Douglas Hofstadter says it as follows:

"The passage leading from vast numbers of received signals to a handful of triggered symbols is a kind of funneling process in which initial input signals are manipulated or "massaged", the results of which selectively trigger further (i.e., more "internal") signals, and so forth. This baton-passing by squads of signals traces out an ever-narrowing pathway in the brain, which winds up triggering a small set of symbols whose identities are of course a subtle function of the original input signals.[...] In the interest of clarity, I have painted too simple a picture of the process of perception, for in reality, there is a great deal of two-way flow. Signals don't propagate solely from the outside inwards, towards symbols; expectations from past experiences simultaneously give rise to signals propagating outwards from certain symbols. There takes place a kind of negotiation between inward-bound and outward-bound signals, and the result is the locking-in of a pathway connecting raw input to symbolic interpretation."