Instruments, or Musical Instruments, is a furniture category that first appeared in Animal Crossing: Wild World. If enough items of the same category are placed in a room, the player will receive an HRA bonus. The category was referred to as "Musical Instruments" in Wild World and City Folk but was shortened to "Instruments" in Animal Crossing: New Leaf.
Animal Crossing: Wild WorldEdit
Animal Crossing: City FolkEdit
Animal Crossing: New LeafEdit