Attack

The tone’s initial moment of sound is percussive.

That percussive sound will either focus or obscure the tone.

A crisp attack acts like a lens; it clarifies. It clarifies because it is short, so short that attack and sustain are experienced as a single, simple, unambiguous event. When the attack is crisp, the ear easily hears where each tone fits in the musical texture. Voice leading becomes unbelievably clear.

A clang attack, on the other hand, approaches noise; it obscures. It obscures because it is so long, lasting several seconds sometimes. The long attack separates attack and sustain into two rhythmically confusing events. Since we play many notes at the same time, this rhythmic confusion obscures voice leading as it is never clear which attack belongs to which tone. (Here is an example)

Clarity in musical tone requires a crisp, short attack.