When I hear music, I stop to rest and think, peaceful, sad, or emotional thoughts. In my mind, I go to a place that has everything I miss from my past. The soft, sharp, and peacefully sound that the violin gives away means peace and reflection.
“I pray to the God within me that He will give me the strength to ask Him the right questions.” -Elie Wiesel, Night
The Nazi's try to control music by not letting Jews play songs that were made in German. The Jews could no longer play the music they desire and they become downhearted. The violin here means sadness of no longer being able to do what you desire.
“Never shall I forget that night, the first night in camp, which has turned my life into one long night, seven times cursed and seven times sealed....Never shall I forget those moments which murdered my God and my soul and turned my dreams to dust. Never shall I forget these things, even if I am condemned to live as long as God Himself. Never.” -Elie Wiesel, Night
You cannot stop not music for it will always be in memories even if the everything is gone. When Juliek died and his violin crushed this says that the Nazis are ruthless and cannot see the beauty in things anymore. This says that Juliek wanted to play a piece of Beethoven, the music he loves, to love, hope, and think one last time. Once Juliek desires were done, death took him. His death means his will not to struggle and suffer anymore. Juliek's violin symbols his struggles, resistance, lost of hope, his life, sadness, and death.
“For in the end, it is all about memory, its sources and its magnitude, and, of course, its consequences.” -Elie Wiesel, Night