On the other hand, the choice of Misia as the first major event in this Latin music festival was inspired. The tediously repeated mantra that Mariza is the "queen of fado" has made a whole generation of concertgoers think that this Portuguese art form means extravagant hairdos, flamboyant ball dresses and clouds of blue mist. Mariza has a lovely voice, but she is a marketing product. Misia, who has been around longer but without the benefit of big-label support, is a reminder of what fado really is. It is not about sex, and it is not for dancing to: it is about the voice, pure and simple. In the traditional café set-up, the singer is flanked by two accompanists on Portuguese and Spanish guitars and performs with a minimum of movement. Fado reflects powerful emotions kept under tight restraint: it is fuelled by tension and release.
Misia chose to perform beneath a photo of an empty white bed with a red telephone - apt symbolism for music about love and loss. And she came on in teasing garb: black-leather jacket and miniskirt, a spray of scarlet berries at her throat, and bright-scarlet gloves. This vampire eroticism was reinforced by her opening song, a triumphant celebration of sexual ownership. But then the gloves came off and she got down to business, singing fados by the dozen in her uniquely suggestive mode.
The lyrics were important, but her virtuosity was the key: whether spinning out delicate threads of melody, or blasting the back of the stalls, or choking on pent-up emotion, she commanded absolute attention. Subtle amplification allowed us to savour every nuance of her interaction with the band. A silvery Portuguese guitar sang out beautifully over the mellower strings below; plus piano, plus violin, plus for the tangos, she added an accordion. Queen of Fado? Long live Misia.
Spilling over into the Barbican, this festival brought the Queen of Mex-Mix back to London: Lila Downs, combining Scots and Mixtec parentage, championing the indigenous music of her adoptive Mexico, and possessor of the most extraordinary voice in Latin America. Mexicans in the audience were singing along as soon as she appeared like a bird of paradise in her village finery, and as song after song extolled the virtues of firewater, the evening became a happy riot. Downs, like Misia, had a new CD to sell, and with her band beating up a storm around her, this performance gave it a wonderful send-off.
Her act has become wilder and more unbuttoned since she was last in London, and her voice runs an even greater gamut. Extremes of pain and pleasure are her leitmotifs: unrequited love, colonial oppression and the sustaining qualities of communal life. "This song is dedicated to the shaman women of Juchitan; this is for the women who break their backs working for US companies on the border; this is for all women who cook" - the chocolate-based sauce garnishing one of Mexico's most popular dishes would galvanise the spirits as well as anything overtly political.
There were times when she gurgled drunkenly, or belted out an accusation with chilling force; she was joined in one marvellous number by her whole band singing a cappella, in harmonies that might have come straight out of a South African township. And every so often, she produced an ethereally high sound like a sweet-toned scream. Yes, Mexico is full of mysteries.