Steven Isserlis/Richard Egarr, Pitville Pump Room, Cheltenham <br></br>Christopher Maltman/ Graham Johnson, Lichfield Cathedral

Get outta town - it's a real tonic

There comes a time in a critic's life when you really need to hear something beautiful, important, and familiar; if only to off-set the plethora of good, bad, and middling premieres that early summer brings. But where do you go to find your favourite works – and musicians – at this post-season, pre-Proms time of year? To the M40.

For those in the Midlands, summer music festivals offer that precise package of beautiful, important and familiar – plus some premieres for the more curious listener – at precisely the right time. To the west there's Regency Cheltenham; a wealthy bohemian dowager of a festival with a habit of snapping her garter just when you least expect it. (Cheltenhamians are either a tolerant bunch or too polite to raise eyebrows at their festival's more avant-garde offerings.) To the north, Tudor and Georgian Lichfield; a previously conservative Cathedral and villages based ten-day event that, under its new director, Meurig Bowen, is in the process of reinventing itself as a bright young thing. Both festivals share an Antipodean flavour; Cheltenham having joined forces with the Sydney Festival, Lichfield's formerly Sydney-based director being on a mission to challenge Old World prejudices about New World music, New World performers, and, er, Prog Rock. Both feature performances by Australian ensembles, and works by Australia's wonderful and (in this country, at least) undeservedly overlooked composer, Peter Sculthorpe. Both also offered exactly the tonic I so desperately needed this week: Bach (in Cheltenham) and Schubert (at Lichfield), performed by the respective partnerships of Steven Isserlis and Richard Egarr, and Christopher Maltman and Graham Johnson.

Call it chutzpah or insouciance, performing your first ever concert as a duo at a venue as prestigious as the Pitville Pump Room requires considerable confidence. Then again, to even conjure a duo like this one requires nerve. A cellist best known for core and modern concerto repertoire and a Netherlands-based, Cambridge-educated harpsichordist famous for painstakingly researched period performance might seen an unlikely match, but no-one at Tuesday night's concert of Bach, Handel and Scarlatti sonatas and suites – or who caught the subsequent Radio 3 broadcast of – could think of the Isserlis and Egarr duo as a mere experiment. Whether through long hours of rehearsal or natural musical chemistry or both, this is a partnership that draws the best from each individual; lending clearer, leaner articulation to Isserlis's glowing, rapturous, open-hearted tone, and adding weight and breadth to Egarr's miraculously detailed, inventive and stylish keyboard playing.

If at times Isserlis and Egarr seemed like two unselfconscious children playing a game of physical and imaginative complexity beyond the watching adults' comprehension, their programme likewise verged on the cheeky. Though all of the works were composed in the late teens and early twenties of the 18th century – by three composers born in the same year (1685) – not one of their chosen duets was actually scored for cello and harpsichord. Bach's three Sonatas in G, G minor, and D were in fact written for viola da gamba and harpsichord, whereas Scarlatti's Sonata in D minor is a partially successful transposition (by Isserlis) for cello and harpsichord of a highly persuasive translation (by musicologist Lionel Salter) for violin and harpsichord of a work for solo keyboard. Did it matter? In the third movement of the Scarlatti, it did (the counterpoint in the Vivace – Allegro – Vivace is too tightly scored for the melody to sing down an octave). In the Bach, much to my surprise, it did not. After a few minutes adjustment to a radically altered dynamic balance between the two instruments, querulous issues of authenticity disappeared. But how can you fret about period style when scalic exclamations from keyboard and strings have such innocence and playfulness and form such a natural, responsive dialogue?

But that's Bach. Like a raincoat that's funky, elegant or down-right slutty – depending on what, if anything, you choose to wear with it – his music is uniquely adaptable. (An idea proved by viola da gamba player Paolo Pandolfo's recording of the Cello Suites, pianist Glenn Gould's first recording of the Goldberg Variations, and many, many others.) Yes, there are limits – over-egged vibrato and ignorance of harmonic structure will hamper music of any period – but prejudices over instrumentation, string materials and bow length fly out of the window when a player allows, rather than forces, the music to sing and speak. The accent of this duo was idiosyncratic – rhapsodically improvisatory, almost mittel-European in intensity – but their delivery was connective, clear and communicative. Could Isserlis and Egarr signal an end to the 30-year gang-war between gut and metal musicians? An entente between authentic and industrial? I don't know but this was an intoxicating debut and I can't wait to hear more from them.

I daresay a nobler critic might have gone to one of Lichfield's more unusual programmes but an opportunity to hear Christopher Maltman singing Die Schöne Müllerin seemed too good to miss, even in the tricky acoustic of Lichfield Cathedral's Lady Chapel. And so it was, as Maltman's Schubert proved as shocking, beautiful, unnerving and provocative an account as one could imagine. Had he seen Simon Keenlyside's extraordinary Winterreise at the Wigmore Hall earlier this year? Or was it simply the presence of an accompanist common to both recitals; Graham Johnson, now worryingly inflexible of touch but still a formidable musical presence.

The commonality of these two works has been much discussed, but never have I had quite such a clear sense of the young narrator of Die Schöne Müllerin being the same character as the misanthropic suicide of the later song-cycle. In Maltman's premonitory reading, disappointment, mania, mistrust, obsession and bitterness are there from the start; implying that the apparent romance between apprentice and miller's daughter may be closer to a stalker's fantasy, and making Schubert's painstaking, deceptively innocent build-up to the terrifying overt pugilism of Der Jäger as menacing as a thriller. With gleaming, rich, scalpel-accurate tones and an incisive, suspenseful reading of Wilhelm Müller's remarkable poetry, Maltman's interpretation is now second to none.

a.picard@independent.co.uk

Cheltenham International Festival of Music (01242 227979) continues to 21 July. Lichfield Festival finishes today with Sung Eucharist and Choral Evensong in the Cathedral