OAE/Zehetmair, Queen Elizabeth Hall, London<img src="http://www.independent.co.uk/template/ver/gfx/fourstar.gif"></img >

We tend to think of the tightly argued four-movement symphonies of Haydn and Beethoven as having established the symphonic norm for all time. But there was a period in the mid-18th century when the symphony might have evolved along the more soloistic lines of the so-called sinfonia concertante. Haydn's Symphony No 31 in D major, Horn Signal, composed in 1765 during his first years as music director for the Esterhazy family, is such a work.

Its spur was evidently the exceptional availability of no less than four outstanding horn players. But its amiable variation-form finale also runs to solo spots for cello, flute, violin and even double bass - all enchantingly taken in this rare hearing from the Orchestra of the Age of Enlightenment under Thomas Zehetmair. The rarity is at least partly due to the difficulty of the often fiendishly high horn parts. It was wonderful to hear them delivered so securely on the natural horns of Haydn's time in all their brazen glory.

After such alfresco pleasures, Mozart's lucid, gentle Piano Concerto No 27 in B flat major, K595, came over as positively intimate, as distilled in the delicate fortepiano tones of the Russian virtuoso Alexei Lubimov. Yet, despite the presence of a substantial orchestra, scarcely a note was obscured, thanks to Lubimov's inventive decoration of Mozart's repeat-phrases and quirky pointing of his more lively rhythms - while Zehetmair found just the right balance of restraint during the solos and luminous fullness in the tuttis.

And so to Schubert's Symphony No 4 in C minor, Tragic, composed at 19 and indebted, like all his early symphonies, to Haydn and Mozart - though, in this instance, apparently aspiring to the C minor pathos of Beethoven. Actually, the more driving "tragic" mode comes over as a bit of a try-on, from which Schubert is constantly escaping into more congenial material, while the most personal moments often come in the transitions, such as the haunting lead back from the slow movement's first episode.

Zehetmair could not always disguise the squareness of the principal themes, but unfolded the slow movement's wayward progress beautifully and developed a fizzing momentum in the finale - delighting the sell-out audience that the OAE almost invariably, and deservedly, seems to command these days.