It is a smaller room with engaged columns and capitals which is also known as the oratory because in 1975 it was made into a chapel.
On the walls stand two superb tombstones, one from the 15th century and the second one from the 17th century. They represent two Vaucelles abbots.
Every morning the monks used to gather around the prior in this room so that he could give them the instructions for the day. It was the only place where practical conversations could take place. Total silence was required everywhere else. The organization of a monastic day is explained with great precision in the 48th chapter of the Rule of Saint Benedict.
The original construction of the auditorium was slightly altered in 1550. The stalls come from a Cistercian abbey near Loos, the Esquermes monastery for women, which had inherited them after the French Revolution and is now a home for children.