The great organ

• 1468: Hélie de Bourdeilles, Archbishop of Tours, gives an organ to the cathedral.
• 1543-1560: construction of another organ, which was damaged in 1562 by the Protestants during the Wars of Religion and was placed on a wooden gallery at the end of the south arm of the transept.
• This organ was then regularly maintained and improved, sometimes by famous organ builders: Hammerbeck, J. B. Isnard, François-Henri Clicquot, Joseph Merklin (in 1875).
• 1927-1929: the organ is entirely rebuilt by Georges Gioton. The case of the Rückpositiv (chair organ) is emptied of its pipes to house keyboards.
• 1990-1996: a new reconstruction by the Strasbourg organ builder Daniel Kern. The Rückpositiv gets its pipes back. The organ has three manuals and a pedalboard, 56 stops (different tones) and 3,928 pipes.
• Since 1984, the organ case has been listed as a Monument Historique (historic monument), along with 818 old pipes. The case is made of oak.
• Since 1979, the organ has been promoted by the Organo Pleno association.

The "Organo Pleno" association

This was the expression used in Germany in the time of Johann Sebastian Bach for the registration using the full power of the organ. It is also the name adopted in 1979 by the Association des amis de l'orgue de la cathédrale (Friends of the Cathedral Organ). Founded on the initiative of Canon René Délémontex, Jean-Michel Vaccaro and Gérard Proust, and later supported by Canon Marc Hamon, it set itself the goal of persuading the public authorities to rebuild the great organ. The great organ is played during services.

Since the spring of 1996, "Organo Pleno" has devoted itself to showcasing the new instrument built by the organ builder Daniel Kern, and to promoting the organ in all its forms. In August and September, organ concerts are given in the cathedral