MUSIC / Mauve satin, spiritual repose: Adrian Jack on the opening recitals in Tatiana Nikolaeva's cycle of the Bach 48 Preludes and Fugues at the Wigmore Hall

THREE years ago, Tatiana Nikolaeva could barely fill half the Wigmore Hall. Earlier this week, the first two of her four recitals devoted to Bach's 48 Preludes and Fugues were sold out. The solid warmth of applause as this homely 68-year-old appeared on Monday, wrapped in violet satin, proclaimed her current status as a monstre sacre. Her Gramophone Award in 1991 and recent television appearance have no doubt helped.

Nikolaeva deserves every bit of her audiences' affection, though there are some who protest that her playing lacks either magic or electricity, and truth to tell, a few of the first 24 Preludes and Fugues on Monday and Tuesday found her below her best. In the nimble right hand part of the D major Prelude, though she had played no fewer than four Preludes and Fugues with perfect poise before it, she sounded under-exercised, as if she needed time to warm up, and the Presto at the end of the E minor Prelude was crudely heavy-handed.

Yet these seemed unimportant lapses in the context of so much warm, robust yet thoughtful playing, showing the kind of unforced confidence in the music's character that defies description, not to mention an unfailingly clear exposition of its contrapuntal textures. For, bar the occasional fluffs, every voice was balanced surely, with a minimum of strain or artifice.

Fugue subjects were mostly strongly announced on every entry, and in the long B minor Fugue they were contrasted emphatically with much quieter episodes. The preceding Prelude was quiet and smooth throughout, and although there are distinct possibilities of pointing up the stern canonic structure of the right hand against the more swiftly travelling left-hand accompaniment, Nikolaeva ignored them - who's to say she is wrong?

Dramatic articulation is not to her taste, although she began the subject of the A major Fugue with an almost comical stab each time it occurred. The grand chords marking the sequential final section of the B flat major Prelude were unexpectedly quiet, yet both lovely and effective. Her use of light articulation in the extended A minor Fugue immediately before that was less convincing, and seemed to reduce the music's architectural power, resulting in a general effect that was choppy, though elsewhere, in the E flat major and F minor Preludes, Nikolaeva made generous use of the right pedal to give an almost misty dreaminess. She never let the pedal obscure the counterpoint of a fugue.

Some of the best things were the plainest, like the opening C major Prelude, whose familiar simplicity drives many pianists to desperate lengths in exquisite ivory-tickling. But Nikolaeva can be limpid and melting, too, as she demonstrated in the F sharp major Prelude that opened Tuesday's recital. The nobly formalised pathos of the E flat minor Prelude was equally sensitive, poignant without heaviness, though Nikolaeva cut corners in the note values, which may have helped her keep the music flowing at the expense of an idiomatic rhythmic precision.

Nikolaeva's sovereign virtue is her air of mellow spiritual repose. If this means she lacks the tight, springy rhythms and exquisite colouring of younger pianists, and particularly of some of her compatriots, it's no loss because of what we gain from the unselfconscious bounty of her expressiveness. In her hands, Bach is flesh and blood, a solid God-fearing fellow whom no one need be in awe of, though most of us must find irresistibly lovable. On Monday Nikolaeva was unfortunate in losing her concentration in the Courante of the fourth French Suite, all the movements of which she played as an encore. The following night she ended with Myra Hess's arrangement of Jesu, joy of man's desiring and perhaps let her sense of decorum slip a shade in loosely billowing rhythms, lavish pedalling and an enormous rallentando which recalled the coffee house rather than the church. Dame Myra might have raised an eyebrow.

Remaining programmes: tonight and tomorrow, 7.30pm, Wigmore Hall (returns only)