Arturo Toscanini regarded Ravel’s orchestration of Mussorgsky’s Pictures at an Exhibition as a genuine treatise on instrumentation. Scored for the same instrumental forces as La Valse, Ravel’s version quickly established itself ahead of all the many competing orchestrations of Mussorgsky’s piano suite. In conductor François-Xavier Roth’s view, La Valse and Pictures together represent the peak of Ravel’s output for the orchestra of his time, as the musicians of the period-instruments ensemble Les Siècles reconstruct it for us today.