It's all very well enjoying the sound of Cecilia Bartoli on CD executing another astonishing vocal feat, showing off the virtuosity for which she's become famous, and displaying the passionate artistry that has earned her such a reputation. But there is nothing quite like hearing her live in concert.
Records can hide tiny flaws, retakes make the tiniest detail perfect and technology can improve every nuance but in a recital all is revealed. Bartoli has little to fear from such exposure even if the voice shows the merest signs of fraying since her last British recital appearances. On a concert platform, with nostrils flaring, pony-tail tossing and arms twitching, she offers as much to see as to hear.
Continuing her detective work, bringing forgotten or neglected composers from dusty library to international prominence, Bartoli has based her current project on works composed during the early 18th century when a Papal decree prohibited certain music. There's a dangerous edge to this music the way she sings it and Pope Clement XI must be spinning in his grave.
Opera was definitely out, with anything theatrical denounced as a bringer of sin and damnation. But thanks to some cunning priests - doubling as poets and patrons - composers were enabled to write in an operatic style. And musicians, accustomed to investing any music they were given with drama, expression and sexiness, sang it with full operatic extravagance.
In the opera proibita which emerged - settings of texts dealing with piety, martyrdom, and religious zeal - sacred subject meets sensuous singer.
Bartoli's coloratura mezzo colours may not be quite the same as the castrati of the time but her silvery voice and alternately flamboyant style and captivating pianissimo make for riveting listening. Arias by Scarlatti and Caldara make tremendous demands in terms of breath control and vocal agility but, in Bartoli's interpretation, they're much more than mere sprays of glittering fireworks.
Most of this repertoire is completely unknown but Handel was a great one for borrowing from himself so that the tune of "Lascia la spina" is now familiar from his later Rinaldo.
Seldom has it sounded so meltingly beautiful. As well as some vigorous instrumental spots, vitally performed by the fresh-sounding Basel Chamber Orchestra, there were opportunities for oboe and trumpet to duet triumphantly in tongue-fluttering, finger-twiddling dialogue with Bartoli.
Julia Schröder on first violin proved a flexible partner to Bartoli's whimsical solo line yet it was the singer who was really leading the orchestra, with her whole body. The throbbing "Si piangete pupille dolenti" was perhaps the most heart stopping example of Bartoli's complete artistry, at least until the first of her encores, "Ombra mai fu".
Three of the vocal numbers including the magical "Io sperai trovar nel vero" are not on the Opera proibita CD which, surprisingly, has topped the pop charts in some parts of Europe. Singers may come and singers may go but Bartoli is a truly amazing vocal phenomenon.