Simplify the following text for a Grade 6 native English-speaking person.
Original: ClÃ rambault became the organist at the church of the Grands-Augustins and entered the service of Madame de Maintenon .
Simplified: He became the organist at the church of the Grands-Augustins and then at Saint-Sulpice . He worked for Madame de Maintenon who arranged concerts for King Louis XIV .