The organ is tuned at 415 to match the temperament of the Schlick organ. It is comprised of 2 keyboards with 56 keys each, and a pedal of 30 notes, 18 ranks for 29 registers. Dominique Thomas uses the system of stops called 'baladeurs'; a process which lets a player use an organ with 18 stops as if it contained 29! The instrument was created according to criteria established from a study of organs built or modified in the 18th century, under the direction of J-S Bach.