This 1967 recording bears witness to Carlos Kleibers sole encounter with Gustav Mahler. Prior to this, he had never conducted a work by the composer, and would never do so again. Given how extremely selective was his choice of repertoire, this was certainly an exceptional case. Within the context of the Mahler Festival, he therefore had to bow to the pressures of what was, by his standards, an extremely short rehearsal period of four rehearsals for Das Lied von der Erde. At the time the performance was thus considered thoroughly controversial. Past releases of this particular Das Lied von der Erde recording have received high praise in various Kleiber Internet forums. But these recordings were of such poor quality that knowledgeable Kleiber fans simply could not listen to them. Judging by the condition of the source material, we were working with a second or even a third generation of the original recording. This became the crucial assignment for our recording engineer; to bring new life to this historic recording was certainly a challenge.