LDV49.1

74 MESSIAEN_THE ORGAN WORKS In the Chants d’oiseaux from the Livre d’Orgue , the marking ‘Plein-jeu et Clairon’, requested for the call of the song thrush, is a good illustration of this point. From the point of view of the ‘ideal’ sound, one could say: ‘Plein-jeu = extreme treble’ and ‘Clairon = brilliant and intense sonority’, an effect something like the tone of the E flat clarinet. From the point of view of the actual sound, we can make the following remarks: the Plein-jeu, with its ‘breaks’ back to lower ranks, blurs the pitches; and the Clairon, in this tessitura, does not have the expected brilliance. Performers therefore find themselves facedwith a difficulty.Will they content themselveswith the letter orwill they try to discern the composer’s intention? In addition to registration, that intention is indicated by the dynamicmarking (in this case ff ). The dynamics (which Messiaen always marked meticulously) are at least as important as, if not more important than the proposed registrations. On this subject we may cite the opening of Les Bergers (from La Nativité ): the right-hand part is marked pp while the left hand is marked mf . Equally characteristic is the registration of the beginning of La Vierge et l’Enfant ( La Nativité ): here, the Quintaton is mf while Flûte 4 and Nasard are pp .