Question

whose big voice turns to childish treble

Answer 1

from which chapter this question is

Answer 2

The line has been taken from the poem of William Shakespeare which is called Seven Ages of a Man.

The line his manly voice changing into a treble describes some of the humiliations one faces after aging.

This line refers to the voice of the man who has gone through so much in his life and finally during his old age he has again turned into a child.