Allows us to identify each instrument's distinctive qualities. it allows us to hear a difference in sound between a piano, clarinet, erhu, voice, or any sound.

The answer is Octave a symbol used to notate a pitch and its duration. Note is also used to identify a pitch or a tone. Octave is the interval between one musical pitch and another with half or double its frequency. It is defined by ANSI as the unit of frequency level when the base of the logarithm is two.

so you know what happened be fore you were alive

explanation:

the above statement/question is (true);