Aristide Cavaillé-Coll was a French organ builder. He has the reputation of being the most distinguished organ builder of the 19th century. He pioneered innovations in the art and science of organ building that permeated the profession and influenced the course of organ building, composing and improvising through the early 20th century.

The symphonic organ is a style of pipe organ that flourished during the first three decades of the 20th century in town halls and other secular public venues, particularly in the United States and the United Kingdom. It has roots in 19th-century Europe, and is a variation of the classical pipe organ. It features expanded capabilities, with many pipes imitative of orchestral instruments, and with multiple expressive divisions and organ console controls for seamlessly adjusting volume and tone, generally with electric organ actions and winding. These expansions let the organist approximate a conductor's power to shape the tonal textures of Romantic music and orchestral transcriptions. These organs are generally concert instruments as opposed to church organs. The symphonic organ has seen a revival in the US, Europe and Japan, particularly since the 1980s.