The collection of letters from a number of composers and scores by Brahms is since 2000 part of the collection of the Brahms-Institut. Avé-Lallemant, who played the violin himself, possessed the Cremonese violin of Prince Louis Ferdinand of Prussia (1772–1806). Apart from being a soldier in the Napoleonic wars, Louis Ferdinand was also a gifted musician and composer. The prince brought his violin also to military campaigns. He bequeathed it to his friend, Avé-Lallemant's father, the evening before his death in the Battle of Saalfeld with the words: ″In case that I will not return from the battle.″