Hilliard Ensemble, Wigmore Hall, London

It is 30 years since the young baritone Paul Hillier convened a handful of fellow singers to explore early vocal repertoire.

It is 30 years since the young baritone Paul Hillier convened a handful of fellow singers to explore early vocal repertoire. Since then, the Hilliard Ensemble has not only set unprecedented standards for purity of tone, blend of texture and security of intonation in consort singing, but inspired a whole gamut of comparable outfits, from Gothic Voices to the Orlando Consort.

Hillier himself departed to the United States some 14 years ago to be replaced by Gordon Jones, but that plangent countertenor David James and the learned tenor Rogers Covey-Crump go back almost to the beginning, while John Potter has only recently been succeeded by the radiant young tenor Steven Harrold. Such continuity tells. The moment the four launched into the opening programme of their three-concert celebration at the Wigmore Hall, it was evident they are as good as ever.

Unlike the complete Gesualdo Tenebrae Responsories for Good Friday comprising their second concert, or the interweaving of Bach and Arvo Pärt of the third, the opening bill was a typical medieval-to-modern collage of no less than 10 composers. They began with one of the most enduring of their many commissions, The Hilliard Songbook by Piers Hellawell, a setting of extracts from a treatise on painting by the Elizabethan miniaturist Nicolas Hilliard, alternating fine-spun monodies and densely luminous close harmonies evoking the colours Hilliard describes.

After four nicely contrasted early Tudor pieces by Fayrfax, Cornysh and Anon, the Hilliards launched into the 18-minute span of one of their most recent commissions, Cathedral in the Thrashing Rain, by the American composer Stephen Hartke. The text, by the Japanese poet Takamura Kotaro, consists of the meditations of a Japanese tourist as he contemplates Notre Dame in Paris during a furious storm. Hartke's setting quick-shuffles a vast range of harmonies and textures from modern all the way back to jigging echoes of the 12th century manner of Pérotin, demanding a kind of ultimate virtuosity in consort singing to which the Hilliards rose peerlessly.

The second half reverted to the 14th century with four settings by Machaut, ranging from the languorous strangeness of the polytextual motet Fins cuers doulz to the leaping polyrhythms of Plange, regni respublica. Perhaps, for once, the Hilliards rather pulled their punches in the latter, though they more than made amends in the fierce directness with which they put over the initial onslaught of James MacMillan's ...here in hiding..., with its gamut of vocal special effects to round off the concert.

The high point, however, was their tender treatment of Ah, gentle Jesu, a verse-refrain part song by the early Tudor composer Sheryngham, evoking a dialogue between a sinner and the crucified Christ, that palpably moved a capacity audience. With artistry of this calibre, no wonder early repertoire comes up so expressively. And no wonder contemporary composers are queuing up to write for them.