The opening is all innocence, touching but held back as befits a hushed lullaby. It is as if the singer cannot bear to wake her beloved and has shyly shifted into a backwater tonality, away from the brightness of G major, in order to soothe his dreams. She is much less of a minx than the Spanish girl in Wolf's In dem Schatten meiner Locken—a song of superficially similar scenario. Vivacity enters the music just before the song of the nightingale itself (and the words 'und ich kann fröhlich sein und scherzen') but the jauntiness of the little birdsong piano interlude should be tempered by the accompanist's sense of occasion—the nightingale is a small bird. The sudden change to G minor, and a succession of D's repeated in the vocal line at 'Nachtigall, ach!' is quite simply heart-stopping despite (perhaps because of) the tried-and-trusted alternation of tonic and dominant harmonies. But now wonder piles on wonder. The effect of a poised high G harmonised on E flat for the word 'Amor' is extraordinary enough; what has won the composer many a slavish admirer is the way this music melts back into the second inversion of G major during the held high note, which then paves the way for a beautiful descent into the tonic in root position on the word 'wach'. One such Schubert devotee was Hugo Wolf whose songs of hushed religious awe, and shy and exquisite evocations of nature owe much to the lessons of this masterpiece. Thanks to a song like An die Nachtigall the influence of Wagner on Wolf's output was counterbalanced and refined by an echo of Schubertian simplicity.
from notes by Graham Johnson © 1993