The two organs are world-famous. The smaller one, called the "Koororgel", was built in 1511 by Jan van Covelens, and is built against the North wall of the church. It is the oldest playable organ in the Netherlands. The larger organ at the west end of the church is one of the most famous, significant and beautiful organs in the world. It was built by Jacobus Caltus van Hagerbeer, finished in 1645. The magnificent casework, which unusually stretches from floor to vault and makes the organ part of the architecture of the church, was designed by Jacob van Campen, a leading architect of the time. The enormous canvas shutters were painted by Caesar van Everdingen. The organ was rebuilt in 1723 by Frans Caspar Schnitger. He left the casework much as it was, but created an organ in the North German style within the old case. He reused much of the old fluework, but all the mixtures and reeds were new. The organ has not been changed much since then, and is rare in that 90 percent of the original material, pipework, action, soundboards, case, survives. As such it is one of the most important organs in the world. It is the subject of a documentary made in 2013 and released on DVD by Fugue State Films as "Alkmaar: The Organs of the Laurenskerk".
Carillon
The hour bell was made by Casparus and Johannes Moer in 1525, with a diameter or 130 cm. tone Cis1. ±1950 kg. The bell was given by the abbot of the monastery in Egmond near Alkmaar. The text on the bell: Translation in English: The carillon under the bourdon has 35 bells. The largest 16 by Melchior de Haze were made for this turret. 12 smaller bells from de Waag also cast by M. de Haze, and 7 modern bells by Eijsbouts. In 2014 the turret is undergoing restoration; the bell part is by Clock o Matic from Holsbeek Belgium.
Current function
The church is formally owned by the "Stichting Behoud Monumentale Kerken Alkmaar", which conducts restoration activities and rents it out for weddings and concerts, but also facilitates various cultural initiatives of the city. The main church is open to visitors at no charge. A charge is payable to go into the upper levels and outer viewing areas. The church is currently home to the Alkmaar Altarpiece. A bar has been added into the southern transept.
