Yusa / Lila Downs / Susana Baca, Royal Festival Hall London

You can generally make two predictions about world-music concerts in big venues. First, the performers will have a CD to sell. Second, what you hear live will - in strictly musical terms - be less satisfying than the CD.

This heavily promoted encounter with three Latin divas sounded like triple trouble, but proved to be anything but. On came Yusa from Havana, in white robe and shades and with her hair topiarised flat like a beret. Threading her way through a forest of instruments, she launched straight into a ballad. This girl is a real musician - she trained on piano and bass, as well as on tres - and the adventurous chord-progressions she extracted from her guitar instantly reinforced the point.

By turns singing, roaring and wafting across the footlights like an exhalation, this acoustic instrument was all the backing she needed for her Stevie Wonder-ish voice. These were her own dreamy songs from the spirit-haunted shores of the Caribbean, and she made us hang on every note. When she took her leave, after 25 captivating minutes, the whole hall sighed regretfully.

The stage then filled with musicians to accompany Lila Downs, best known for her riveting soundtrack to Frida. Like the artist-heroine whose voice she articulated, Lila Downs hails from Mexico, and her style is village rumbustiousness crossed with rebellion.

Banging her side-drum beneath videos of slaves on American-owned plantations, she beat up an anti-imperialist storm. Her band showed themselves to be multi-talented, with the sax player taking time off to juggle and the harpist Celso Duarte doing virtuoso stuff on violin and charanga.

But the miracle was her voice. She trained as an opera singer, but that doesn't explain her astonishing range of sounds, or the time she can hold a note. Her speaking voice is light and girlish, but her singing voice is an octave lower, sometimes two, and of a thrillingly resonant timbre. Her "song for the dead" was exultant rather than morbid. The songs she'd first sung in bars now became marvels of condensed expression: art of a very high order.

Finally, Susana Baca appeared, a grande dame in diaphanous drapes, and carved out a lovely stillness in the supercharged atmosphere. Her band, too, was deftly accomplished, but its volume was held in check to allow her to set up sweet confidentiality with the audience. With the aid of her Instituto Negrocontinuo, she campaigns tirelessly on behalf of the music she grew up singing, to her father's accompaniment, in her Peruvian village. This wonderful concert would have converted anyone to Peru's gentle variants on Cuban grooves. Those who missed it can buy three outstanding CDs: Yusa (Tumi), Una Sangre (EMI), and Lo mejor de Susana Baca (Luaka Bop).