''In my opinion the first and most sacred duty of a song-writer is to observe the maximum of fidelity to the prosody of the text that he is setting.'' Weber was writing in defence of a number he composed for an obscure play, but his words can stand as an apologia for his 90-odd songs. His contribution to German song has been underrated, for his ideas were different from those of his contemporaries. Time and again he succeeded in the aim he once expressed to Friedrich Wieck, ''to render my poet truly and correctly declaimed so as to produce new melodic forms''; and the beauty and originality of these has not been sufficiently appreciated.
Fischer-Dieskau used to resist suggestions that he might take up Weber's songs, and it is good that he has done so, even late in his career (the disc was recorded in 1991). Always sensitive to words, he now responds with the subtlety of understanding that comes from many years of closeness to German poetry. Only very occasionally is there the powerful emphasis on the single expressive word that sometimes used mar his interpretations, keeping them too near the surface of the poetry. He can still use individual colour marvellously: the tonal painting of 'blue', 'white' and 'brown' in Meine Farben is exquisitely done. But more remarkable, here and in other songs, is the manner in which he follows the novel melodic lines which Weber has contrived out of the poetry. They are not always easy, and many singers tend to restrain the originality, to make the phrasing sound more four-square. Ein steter Kampf is a masterly example; so is Was zieht zu deinem Zauberkreise, one of the few songs in which Weber enters Schubertian territory so are Es sturmt auf der Flur and Liebesgruss aus der Ferne. Not even Fischer-Dieskau can quite bring off the coy Der Kleine Fritz by slightly sending it up (the only hope), and there is something a bit hefty about Reigen, a very funny wedding song full of ''Heissa, lustig!'' and ''Dudel, didel!'' though Hartmut Holl does wonders with the clanking accompaniment. Holl varies his tone so much here from the warmth and depth of his touch elsewhere that I wonder if the engineers did not take a small hand: why not?
None of these songs sets great poetry. Weber's verbal sensitivity led him to avoid poetry in which he felt the creative gesture was complete. But these are charming, touching, witty, colourful verses, often by minor figures of Weber's circle, and they drew from him music that heightens their point. Fischer-Dieskau's intelligent artistry could not more eloquently support the praise for Weber from Wilhelm Muller, poet of Die schone Mullerin and Winterreise, as ''master of German song''.'