Sound quality or tone color; characteristic that allows us to distinguish between one instrument and another or identity one singer from another. This element is the tone color of a sound resulting from the overtones. Each voice has a unique tone color that is described using adjectives or metaphors such as "nasally", "resonant", "vibrant", "strident", "high", "low", "breathy", "piercing", "ringing", "rounded", "warm", "mellow", "dark", "bright", "heavy", "light", "vibrato".