Answer: Timbre
Explanation: Timbre in the general sense means something that is originally recognisable by someone or something, that is, a recognisable character. In the musical sense, timbre means a recognisable character, a musical characteristic of an instrument, a recognisable voice or sound. Timbre, therefore, does not depend on the note or duration, loudness, pitch, etc., because each instrument has its own typical sound. So even though two musicians play two different instruments with the same pitch, duration, etc., it can always be distinguished which instrument is in question because each one is based on a specific sound, i.e. timbre.