The organ of St Martin's Church in Aalst (B) was originally built in 1758-63 by Pieter van Peteghem. He was a pupil of Jean-Baptiste Forceville and the progenitor of a famous Flemish organ-building family that was active during four generations between 1733 and 1868. The organ of St Martin's Church was a three-manual instrument with 43 stops on Hauptwerk, Rückpositiv, Echo and Pedal. The disposition was a design by Dieudonné Raick (organist of the cathedral in Antwerp) and Jean-Joseph Boutmy (organist of the cathedral in Ghent). The organ remained largely intact until 1909. In 1909-12, the organ builder Stevens carried out a radical rebuilding, which in effect amounted to a new building in the old case with the reuse of some of the old stops. Everything of the case structure that was in the way of the new organ interior was sawn away without regard to the statics. Only the front side of the Rückpositiv remained. A new positive was installed in the lower case and the previously closed panels on both sides of the old console were replaced by fabric-covered frames. In a fire in 1947, the organ suffered severe water damage. Over the next few years the damage was repaired by Stevens and a new rebuild followed. When the current church restoration began in 2014, the organ had been unplayable for some time due to its poor construction and inferior materials, and the case was in a deplorable state due to the destruction of the statics. Therefore, it was decided to also fundamentally restore the organ.

This organ was one of Pieter van Peteghem's largest and most important instruments and the best rehabilitation of the magnificent case and the preserved historic pipes would be an instrument in the spirit of the original. Therefore, in consultation with the organ committee, the city council and the monument authority, it was decided to take Van Peteghem's concept as the starting point for the restoration. In principle, an almost complete reconstruction of the Hauptwerk and Rückpositiv is planned. The pedal, which was originally independent only in the great octave and then attached to the Hauptwerk up to f0 an octave lower, will now be given a larger range and expanded with two stops useful for performing French and German Baroque music. Instead of the original Echo organ, a Unterpositiv is planned with a disposition extended by several stops. The later opened fillings in the lower case will be closed again, but remain openable as doors. When closed, the Unterpositiv can again be used as an echo, while when open it can serve as a "full-fledged" third movement. The project is now in the planning phase.