Independent consultants ("organ advisers") play an essential role in organ restoration projects. As experts in their field, they are engaged by the owners of instruments (such as church councils) to draw up a restoration plan, supervise the project in consultation with the organ builder in question, and assess the result. Through their key role, consultants often set a significant mark on restorations; they are therefore in a position of considerable responsibility, especially in view of the monumental and valuable nature of many instruments.
The Utrecht Organ Archive is in possession of the archives of the organ consultants Johannes Legêne (1915-1996), Lambert Erné (1915-1971), Maarten Albert Vente (1915-1989), Klaas Bolt (1927-1990) and Abraham Jacobus Kret (1928-1993), who all left an indelible mark on the restoration of world-famous monumental organs in the Netherlands. Their archives reflect views on restoration and conservation from about 1950 onwards. They include official documents (correspondence, contracts etc.) and drafts, records, notes, sketches and suchlike, enabling us to gain thorough knowledge of the thought processes of these consultants.