After a period-instrument reading of the Symphony no.1 that received unanimous acclaim from the critics, Francois-Xavier Roth and Les Siecles return to Mahler. Joined by the luminous voice of Sabine Devieilhe for the famous finale, they offer us their vision of the Fourth Symphony, which in its own way marks the composer's transition to modernity, and reveal unsuspected colours and instrumental balances. We still have much to learn about the polyphonic transparency possible within Mahler's big orchestra!