On hearing a musical note played by a piano and hearing the same musical note played by a tuba.

Qualia

Qualia are the subjective or qualitative properties of experiences. What it feels like, experientially, to see a red rose is different from what it feels like to see a yellow rose. 

Likewise for hearing a musical note played by a piano and hearing the same musical note played by a tuba.

 The qualia of these experiences are what give each of them its characteristic “feel” and also what distinguish them from one another. 

Qualia have traditionally been thought to be intrinsic qualities of experience that are directly available to introspection. However, some philosophers offer theories of qualia that deny one or both of those features.

Paradigm examples of experiences with qualia are perceptual experiences (including nonveridical perceptual experiences like hallucinations) and bodily sensations (such as pain, hunger, and itching). Emotions (like anger, envy, or fear) and moods (like euphoria, ennui, or anxiety) are also usually taken to have qualitative aspects.