THE Armonico Consort, based in Warwickshire, is an ensemble of note. Under the astute leadership and incisive musicianship of its founder, Christopher Monks, it is also responsible for one of the most exciting youth schemes in the country. This is the Armonico Academy, which brings musical training to a vast range of schoolchildren and young people, even beyond the group’s county.

Given Coventry’s accolade of 2021 City of Culture, Armonico plans an initiative to reach out to all schools in Coventry and perhaps beyond. Closely involved in this will be Coventry Cathedral; and it was there (and at three other venues: the Lighthouse, Poole; the Anvil, Basingstoke; and Malvern Theatres) that the ensemble has lately teamed up with the much-recorded Choir of Gonville and Caius College, Cambridge, to perform two extraordinary rare works of the Italian Renaissance.

These proved the highlight of the occasion, even though Armonico’s large gathering ended with Tallis’s 40-part motet Spem in Alium, written for the Duke of Norfolk’s family chapel at Arundel. This, we gather, is likely to have been influenced by the two long-forgotten pioneering works: the stunning 40-part motet Ecce Beatam Lucem, and the Mass of that name, by the Mantua-born Alessandro Striggio (c.1537-92). For some years, he was principal musician to the De’ Medici family in Florence. Touring Europe, he visited England in 1567, just a year after the Mass (1566) was composed.

I found his motet, performed at the end of the first half, the most absorbing and involving work of this concert. Composed not for Italy, but for the royal court in Munich, it flows superbly, is constantly varying, and achieves an astonishing richness with the alternating and interweaving of the parts, and expressiveness of both inner and outer voices.

Oddly, the Tallis, written about four years later — c.1570, it is thought — glorious though it is, seemed a little pallid and repetitive in comparison. This had nothing to do with the very desirable performances (we heard it twice, Caius’s Geoffrey Webber conducting the first), which were rich and resonant, but was because the musical material seemed to grow a little clichéd. Perhaps one should say, in defence, that it was like a constantly turning kaleidoscope.

Much though we admire and rightly love it, it seemed to lack the marvellous tensions and harmonic intensity of, say, Tallis’s O Nata Lux (performed first), or the lovely quality of Byrd’s “Christ, Rising Again From the Dead”, with its heavenly imitations, contributed by the finessed, intelligent, sophisticated, and attentive Coventry Cathedral Choir, inspired by its director, Kerry Beaumont.

An unexpected additional treat was a series of plainsong-influenced sequences by Hildegard of Bingen: an intelligent choice in the first half; for they, whether for men or for soprano with beguiling drone, contrasted magically with the larger works that featured such a flood of voices.

The main focus was, however, the interspersing of the pieces in both halves with the impassioned six sections of Striggio’s Missa Ecco Sì Beato Giorno for five choirs. It felt — and looked — like eight choirs of five voices, strategically placed to marvellous effect. The Coventry acoustic can sometimes be problematic, but, with the seating reversed to obviate the problem, the work swept you off your feet.

The results were never ponderous. At times such “big” works can seem a swizz; for how often does one hear 40 different parts counterpointed? Often (as in the Tallis) parts are doubled or behave antiphonally.

The fascinating Striggio “parody” Mass performed here was thought lost until it was rediscovered by an American scholar in the Bibliothèque Nationale, Paris, in 2005. It was then widely publicised by Robert Hollingworth’s group I Fagiolini and Hervé Niquet’s French ensemble Le Concert Spirituel. Here, just one instrument, a rather atmospheric solo sackbut or Renaissance trombone, was employed. It has even been aired in a BBC Prom, under Peter Phillips.

Especially in the Credo, perhaps, the Mass has a tremendous impact, which, with the conductor’s encouragement, brought out an exciting fullness in the choirs. The first, placed at the front, achieved an often quite delicate and beautifully calibrated ensemble feel, notable in the later sections: the Agnus Dei, intriguingly, goes one better, ascending to 60 voices.

Monks has assembled a polished and enduring professional choir, who listened to each other and gelled marvellously even when the copious constituent units were placed far apart. The sound was terrific. We were dazzled, but also educated, in a rare and overwhelming experience.