For all Ravel's orchestral mastery, only four of his works were conceived as concert works for symphony orchestra: "Rapsodie espagnole", "La valse" and the two concertos. All the other orchestral works were written either for the stage, as in "Daphnis et Chloé", or as a reworking of piano pieces, "Alborada del gracioso" and "Une barque sur l'ocean", ("Miroirs"), "Valses nobles et sentimentales," "Ma mère l'Oye", "Tzigane" (originally for violin and piano) and "Le tombeau de Couperin." In the orchestral versions, the instrumentation generally clarifies the harmonic language of the score and brings sharpness to classical dance rhythms. Occasionally, as in the "Alborada del gracioso", critics have found the later orchestral version less persuasive than the sharp-edged piano original.