The universal praise that this CD has received speaks for itself. Quasthoff and von Otter enjoyed a joint tirumph in their earlier Mahler CD of 'Des Knaben Wudnderhorn," and although their voices are in their late prime, the two singers are equally masterful here. (One should note that Quasthoff's earlier version of the Wayfarer Songs, under Gary Bertini, has been rereleased. It wasn't much noticed on the Capriccio label in 1993, and the conducting is prosaic, but Quasthoff was in phenomenal voice.)
I felt some initial doubt whether Boulez had the tragic intensity that 'Kindertotenlieder' needs -- could he match Barbirolli and Bruno Walter in their classic acocunts with Janet Baker and Kathleen Ferrier? -- but he finds more detail in the score than either, and the Vienna Phil. is incomparable in this music. Boulez and von Otter express a quieter grief than usual, it must be admitted. Their emotion is so genuine and artistically conveyed that comparisons don't matter, though. If only von Otter had been caught ten years earlier when she had the vocal weight and control to sing the extremely difficult last song, 'In diesem Wetter.' Even with close miking she barely has enough voice now.
The Lithuanian mezzo cum dramatic soprano Violetta Urmana is the odd one out, so far as Mahler tradition goes. She doesn't communicate the poetry except in a generalized way, but her vocalizing is alluring. Memories of Baker, Ferrier, Fischer-Dieskau, Ludwig, and Hunt Lieberson aren't effaced by any means. Her biggest challenge is "Ich bin die Welt abhanden gekommen," arguably Mahler's greatest song. Boulez takes a moderate tempo, which helps, and Urmana reaches a bit deeper for emotion, so the result is quite beautiful. Her powerful voice comes in handy for the thrilling climax of 'Um Mitternacht,' the high point of her Ruckert Lieder.
In the end, Quasthoff comes away with highest honors, but von Otter is his equal expressively, and Urmana shines as pure singing.