He is considered to be one of the most talented organists of his time, a gifted improviser, an expert in organ building, a poet in his leisure time and in touch with the theorists of his time.

Titelouze's organ works, printed in 1623 and 1626, are the cornerstones of the French organ school, both in terms of their intrinsic quality and their independence: the last organ pieces published in France were written in 1530 and 1531 by Pierre Attaingnant, and the following ones did not appear until the 1660s (François Roberday). The organists usually improvised on plainsong motifs. The writing of these pieces is based on the alternatim practice ("versets alternés"): a verse sung by the choir, a verse played on the organ or written on the same plainsong. Titelouze uses fugal motifs (also known as recherches, or ricercare), long-note basses over which a flourishing polyphony unfolds, sometimes a little rough to our ears, in a writing that is still modal, well-suited to uneven temperaments and well-stamped stops, and which reveals an assertive and confident composing talent.

These pieces for organ by Titelouze are the first scores of this type printed in France; they constitute a technical achievement, as the typographical composition is so complex. The prefaces to these volumes mention progress in organ building, some theoretical and practical aspects of playing and the use of his music in the liturgy.

[Source: Wikipedia]