Since her arrival on the scene in the mid-80s, the Mississippi-born singer Cassandra Wilson has developed one of the most recognisable and imposing voices in contemporary music. It has flashes of Nina Simone's savage majesty, Abbey Lincoln's forthright intimacy, and a sumptuous contralto register that sometimes suggests a more blues-based Cleo Laine. It would be thrilling to hear Wilson singing the Yellow Pages, yet an obliqueness and reserve seem to prevent her from realising her full potential.
Wilson's early breakthroughs were striking enough, but she would probably have remained on the shelf reserved for jazz buffs had she not changed tack to a blend of postbop and earthy folk-blues over the past five years. This shift to the sound of bottleneck guitars and no horns has put Wilson into the pop and rock columns, so she can now sell out the Festival Hall.
She is currently on tour with material from her Traveling Miles album, a tribute to the late Miles Davis mostly featuring her own lyrics added to themes associated with the trumpeter. The line-up features percussion, two guitars, bass and piano, so it rarely pursues the brittle, blaring, urban clamour of Davis's later bands, instead exploring a dreamier and more ethereal music of spacious intervals, vocalised guitar sounds, and delayed or diverted resolutions to melodies.
Wilson, who is now 43, was a folk singer in an earlier life, and her blues feel was inspired by Robert Johnson, whose work was included in this show.
It is a bold step for her to cel ebrate Davis in such a diffuse and sidelong manner, rather than by the jazzier route adopted in most homages - and her avoidance of the obvious often produced tantalisingly atmospheric effects. But, as on the record, it doesn't always work, partly because Wilson's own vocal cords sometimes seem stretched to only about half their limit, and partly because she treads a dangerously narrow line between patient attention to nuance and the soporific.
A superb drummer, Lionel Cordew, fired up bursts of urgency with light-speed rolls, startling tonal variety and a bumpy propulsiveness that recalled Davis's percussion sections; slide guitarist Kevin Breit often exquisitely blended a jazzy linear style with a hot brew of raw blues chords and arcade-game sound effects, and Wilson's light, dancing handling of subtly adapted Miles classics like ESP and Seven Steps to Heaven were credits to both her and to the source. Yet, as an urgent and inventively spontaneous jam in the encore showed, this fine band has more music in it than the laid-back nature of the project sometimes allows out.
