WNO Chorus and Orchestra, Poppen, St David's Hall, Cardiff

Speaking about the Requiem he composed in 1990 in memory of the London Sinfonietta’s long-time artistic director Michael Vyner, Hans Werner Henze always talked as a believing atheist. “Paradise is here or ought to be,” he insisted, “not later, when nothing else happens;” and “In this world there is no hereafter, only presence: you can meet angels and devils in the street at any time.”

So it was a surprise to find a lot more spiritual power radiating from the three movements of the Requiem that Christoph Poppen conducted in this concert by the Welsh National Opera Chorus and Orchestra than from the Requiem by that good if not over-devout Catholic, W.A. Mozart. The surprise was on a number of levels. Henze’s Requiem is instrumental, not vocal, so the textual meaning of the various movements has to be taken on trust. Like so much Henze, these are rambling, unfocused pieces, with moments of intense beauty amid a prevailing atmosphere of mild self-indulgence.

You might say that the very act of composing a Requiem omitting the words is a kind of special pleading: trading on the sentiment of the words while avoiding their connotations. Perhaps. But all such feelings were swept away on this occasion by the sheer concentration of Poppen’s conducting and the Welsh playing.

Poppen seemed to have decided that one committed Requiem per evening was quite enough

The pieces were well chosen to serve as a memorial to the composer himself, who died three weeks ago at the age of 86. The “Introitus”, with its delicate, reflective ritornelli for solo piano (beautifully played by Simon Phillippo) and harsh outbursts of protest on the brass; the “Agnus Dei”, alternating piano and softly textured string polyphonies; and the “Sanctus”, with its brilliant part for solo trumpet (Dean Wright), echoed from the farthest reaches of the hall by two more trumpets, like the angels summoning the reluctant composer to confront the deity whose existence he denies.

All this was wonderfully stirring, and in an odd way an improvement on the complete, nine-movement Requiem, which tends to overdo the brilliance and the stridency, and, frankly, to go on much too long (more than an hour). Intensity is apt to dissipate in Henze’s longer scores. Here it was firmly maintained, with the help of a touching introductory speech by the conductor (pictured right), claiming Henze, somewhat speculatively, as one of the most important 20th-century composers, and less questionably as a fine human being. Henze had aesthetic enemies, and he had political ones: but I never met a personal one.

After this, Mozart fell unexpectedly flat, despite a polished performance by the chorus and orchestra, and at least one outstanding soloist in the diminutive shape of Elizabeth Watts, recently a fine Fiordiligi under tricky circumstances with WNO. Poppen seemed to have decided that one committed Requiem per evening was quite enough, and scampered through the work as if anxious to prove that Mozart, too, thought the hereafter a mere abstraction. Music that can be transcendent was reduced to mere excellence. The professional chorus sang immaculately, but without the devotion of struggling amateurs; and the other three soloists, less highlit by the music, practically vanished.

The listening mind also wandered. Did Süssmayr really compose so much music of real power: most of the Lacrimosa (pace the concert’s programme note), all of the Benedictus and Agnus Dei? Or was he working from sketches, now lost, by the dying Master himself? After all, the earlier sections of the work certainly existed in score, incomplete in orchestral detail, but fully composed. Süssmayr could work directly on Mozart’s autograph. Sketch material for the later movements would have to be written up and the sketches themselves probably discarded, not out of deviousness or vandalism, but simply because nobody would have thought them worth keeping.

Or was it, as Brahms later alleged, simply rather easy to write music in Mozart’s day? Maybe; but not Mozart’s music.

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