Sonance is the raw material of sound. It surrounds us just as the air surrounds us. It is expressed in terms of frequencies, which we perceive through our ears in divisions referred to as Critical Bands. This leads to our perception/understanding of pitch, of melody of and harmony. It exists even when we perceive silence. Sonance surrounds us constantly. It is a characteristic of sound that give it its “aliveness”.
Perhaps it can be easily understood as timbre, but I thing of sonance and timbre as separate entities. Timbre, to me at least, is a manifestation of sonance.
Over time we have defined the manifestation of sonance along an axis of “good” and “bad”. Sounds that are generally considered pleasant are “consonant”, and those that are unpleasant are “dissonant”. As musicians we organize sonance, whether as individual sounds or collections of sounds, along this axis.
Sonance is where all of the components of hearing/listening converge. We organize sonance using pulse to define its place in time, and delta to define changes in sonance over time. Sonance is the canvas upon which pulse and delta are drawn to create music, but it makes up all forms of human sound-making, speech being one example.