Cavaillé-Coll refers to a renowned French organ-building company founded by César Franck in the 19th century. The firm is celebrated for its innovative designs and high-quality instruments, which have significantly influenced the development of pipe organs in Europe and beyond. The company was established by Charles Cavaillé-Coll, who introduced advancements such as the use of multiple keyboards and improved mechanical systems. Many of their organs are considered masterpieces, and they can be found in cathedrals, concert halls, and churches, showcasing the rich sound and versatility that define their legacy.