Cinquecento is a group of six men who have been mostly devoting themselves for a number of years to rare Renaissance repertoire. Isaac has often been recorded in recent times but this, his longest and most demanding mass, is, I believe, heard here for the first time.

Its original title was Comment peult avoir joye? It is a parody mass on a song popular at the time and arranged for four voices by Josquin, which immediately follows the mass on the disc. Perhaps Isaac met Josquin in Florence when Isaac was working for Lorenzo de’ Medici as one of the singers of San Giovanni. The German title of the four-part mass however is Wohlauff gut Gsell von hinnen, which even I realise does not translate from Comment peult avoir joye? (‘How can one have joy whom fortune oppresses’). Isaac made a contrafactum from the original, a re-texting, and then extended various sections to produce a mass of over forty minutes duration. These eight entirely new sections are in six parts, which was at the time quite unusual. Helpfully, Hyperion has provided twenty-one tracks to cover the work so that, for example, the Credo has five.

The original version dates probably from 1490 and is a typical four-part example. This German version is of a decade later. The melody is often heard in the upper voice which makes following its progress much easier than usual. There is also what to modern ears is a ‘major’ key feel to the work and passages of imitative counterpoint and various types of canon, as in, for example, the third Agnus Dei, and rich harmonies and melodic repetitive patterns as heard in the second Agnus Dei. The effect is of an exquisitely lyrical texture aided by some beautifully poised and expressive singing.

Much of Isaac’s music comes from manuscripts compiled at the Imperial court at the time of Maximilian I (d1519), including the following motets. There are six motets accompanying the mass; one, O decus ecclesiae is in five parts and is extremely substantial. The text is divided into two parts and is in honour of the Virgin. It is based on a six-note hexachord, which can be heard in various broken-down forms in the tenor part. The mode is again one which exudes something approaching the major key, but the second half of the motet has some darker moments and moves between modes, producing some unexpected harmonies and some quite lengthy sequential sections.

Sive vivamus, sive moriamur is for four voices and just consists of one line, ‘Whether we live, whether we die, we are of the Lord’. It is therefore a short motet but one I have returned to a few times. It begins homophonically and then falls into delicious rolling counterpoint. It is freely composed, as is Quis dabit pacem populo timeneti, which is not based on an existing plainchant, largely because it is a memorial to Lorenzo de’ Medici (d1492) which even uses words from Seneca affiliating Lorenzo with classical models of a great and upright warrior and 'Mighty progeny of Phoebus'. Its scoring for four voices is wide-ranging and varied in texture throughout its three sections.

There are three motets based on Gregorian chants; one is the rather solemn five-part Recordare, Jesu Christe. Again, canonic writing is evident with complex counterpoint. Parce, Domine, populo tuo is a simple, short and beautiful motet in four parts with an unidentified cantus firmus in the tenor. Finally, comes Judaea et Jerusalem. This makes a wonderful ending to the disc but if you feel that it might be stylistically, and emotionally different from the rest of these works then you might agree with those, including me, who consider it to be by Jacob Obrecht. Despite its rather solemn feeling, it is a Christmastide motet—‘The Emmanuel will be born’.

The booklet is up to Hyperion’s normal excellent standard with all texts given in clear translations. The recording is rather close but there is a sense of the lovely seventeenth century Charterhouse complex in which the group was luckily enough to able to record.