Halle Orchestra/ Angela Hewitt, Bridgewater Hall, Manchester

The pianist Angela Hewitt is good value. The astute Hallé Orchestra management, quick to take advantage of her potential, not only engaged her as a concerto soloist – directing the orchestra from the keyboard in two works by Bach – but invited her to give a solo recital on the previous evening in the Bridgewater Hall. For a new venture it was encouragingly well supported, suggesting that a cogently devised Hallé recital series could usefully plug a gap in the Manchester market.

Of course, not all soloists are able to introduce music as lucidly as Angela Hewitt, who prefaced her account of Bach's Goldberg Variations with a short illustrated lecture. And few soloists can hold an audience as rapt as she did – coughs were forgotten, mobile phones stilled and no one stirred – as she unfolded the 30 variations with her customary blend of scholarship, technique and brilliant virtuosity. In contrast to the determinedly voiced canons or the lightly fingered dance movements, the aria itself had a mesmeric quality both in its poised introduction and in its meditative return.

The same textural clarity and subtlety in colour characterised her interpretation of Bach's D minor and F minor keyboard concertos with the string section of the Hallé the next evening. While some dispute that the former was ever a concerto for keyboard (least of all for piano), or even that Bach wrote it, Hewitt's account, as responsive to each melodic detail as to each robust statement, firmly dispensed with any such uncertainty. Whatever the arguments, and whatever your idea is of the real Bach, the composer shone through in every bar and it sounded absolutely right.

Not so much directing as leading by example, Hewitt drew exemplary accompaniment from the strings. Led by the excellent Lyn Fletcher, they gave the impression that playing Bach was the most natural thing in the world, although it must be many years since the Hallé programmed a baroque concerto.

If clarity and a calm sense of purpose distinguished the string playing in the concertos, the same applied to the whole orchestra in Webern's coolly expressive arrangement of the "Ricercare" from Bach's Musical Offering, which prefaced the concertos, conducted by Cristian Mandeal.

In a characterful performance of Bartok's Concerto for Orchestra, Mandeal demonstrated an extraordinary affinity with the composer's musical language. Never vulgarising or overstating the details packed into the score – at times introspective, at others extrovert, moments of nostalgia swept aside by a sardonic riposte – Mandeal observed each change of mood as if intuitively. If further evidence were needed of the Hallé's recent return to form, the whispering strings, the stylish precision of the wind and brass instruments (particularly in the second movement "game of pairs") and the muscular swagger of the finale said it all.