Four Impromptus, D.899

It would be difficult to construct an attractive and balanced recital of Schubert and Brahms piano music with not one piece in sonata form and without even a set of variations. Today’s programme is not far off it, however. Of the eighteen pieces represented here, all but one of them are ternary constructions - abbreviated by Brahms or extended by Schubert though they might be - and there are no variations.

The three pieces chosen from Schubert’s first set of Impromptus, D.899, are a revelation of how versatile ternary form can be. The first section of the Allegro in E flat major is itself a ternary construction, enclosing a not quite so carefree episode in the minor. The triplet figuration runs on without interruption towards an abrupt modulation to B minor for the belligerent middle section - which, though only briefly recalled after the reprise of the first section, secures an unexpectedly grim ending in E flat minor. The Andante in G flat is a wonderfully sustained song not quite without words - it is closely related to Schubert’s Schlegel setting Die Gebüsche - which retains its characteristic broken chord accompaniment between melodic line and bass line from the first bar to the last. In spite of its seamless continuity, however, there is a clearly defined middle section where, stirred by the change of harmony to E flat minor, the left hand joins in a passionate duet with the right. Structurally, the Allegretto in A flat major seems to be little different from the Allegro in E flat major. In fact, it is its exact opposite in that the charming melodious first section remains quite unaffected by the dramatic and recklessly modulating middle section in C sharp minor and, on its reprise, waltzes unconcernedly towards its A flat major ending.

Although he was a master in the art of building extended movements on one theme only, Haydn never wrote anything as obsessive in its attachment to its singular material as Schubert’s Impromptu in C minor. It is a miracle of spontaneous development, its march-like theme recurring literally dozens of times and yet scarcely ever in a form in which it has been heard before. Unpredictable in which key it will alight on next, it is similarly unpredictable in mood: the same theme can be grim in C minor, expansively luxuriating in A flat or G major, melanchoy in G minor. Indeed, it is only in the last few bars that, after much vacillation, it settles for a mutedly happy ending in C major.

The other three Impromptus in the present set - which was written in 1827 for a publisher with so little faith in them that he issued only the first two and held the others back until twenty-seven years after the composer’s death - are all in ternary form with dramatically contrasting middle sections. The triplet figuration of the Allegro in E flat runs on without interruption, though not always as cheerfully as it begins, towards an abrupt modulation to B minor for the belligerent middle section. Though only briefly recalled after the reprise of the first section, the B minor material secures an unexpectedly grim ending in E flat minor.

The Andante in G flat is a wonderfully sustained song not quite without words - it is closely related to Schubert’s Schlegel setting Die Gebüsche - which retains its characteristic broken chord accompaniment between melodic line and bass line from the first bar to the last. In spite of its seamless continuity, however, there is a clearly defined middle section where, stirred by the change of harmony to E flat minor, the left hand joins in a passionate duet with the right.

Structurally, the Allegretto in A flat major seems to be little different from the Allegro in E flat major. In fact, it is its exact opposite in the sense that the charming melodious first section remains quite unaffected by the dramatic and recklessly modulating middle section in C sharp minor. On its reprise it waltzes unconcernedly towards the A flat major ending as though nothing had happened in the meantime.