“Diptyque” (Diptych)
for Organ and Strings

To Hervé Desarbre and Jean Thorel
2002 - 2003
Duration: around 12 minutes
Commission from the “Ensemble Orchestral Stringendo” (EOS)
First performance on 03/01/2004 at Notre-Dame du Val-de-Grâce (Paris)

This work was composed at the request of Jean Thorel, the director and conductor of EOS, and Hervé Desarbre, the musician responsible for the Cavaillé-Coll organ of “Notre-Dame du Val-de-Grâce” in Paris. It is to be included in the 2003 programme of monthly concerts they jointly organize in this church.
Ten string instruments are required:
- 3 first violins
- 2 second violins
- 2 violas
- 2 cellos
- 1 double bass
The two parts of the Diptych are complementary to each other.
Rather than a concerto, it is simply a piece for organ and strings.
The music, above all melodic, is based on modes.
It is supported by different scales or short cells, either diatonic or not, that are subjected to a work on modality and polymodality.
In the second part, the repetition of a single characteristic cell in transposition leads to large scales extending over one to two octaves or more.
From these elements harmonic fields arise, with carefully chosen harmonic colouring.
Concisely built, both of the movements unfold their form in their own logical way.
However one can remark in the first one some characteristic gestures that have their equivalent in the second one. These elements of similarity between the two parts ensure their cohesion. Principles of symmetry have been applied to every level of the composition.
The first movement starts with an evocation of bells ringing and reverberating. Then the organ in regular pace unrolls a series of double notes upon which an intense, expressive song, a kind of lamentation in vocal style, is solemnly developed by the string instruments. Later, in a varied way, these roles are inversed, but the melody remains suspended, to find its conclusion in the next part.
The second movement unfolds as a convulsive incantation-like song of the organ. The strings assume the role of supporting this long obsessive melody and comment on it.