Tenors play lovers; basses play villains. It’s not an infallible rule, but close. So Bryn Terfel, that Welsh man-mountain of a bass-baritone, has chosen to make a virtue (or at least a CD and UK tour) out of necessity, and put together a whole show of arias written for opera’s bad boys. Similar things were done by past greats, of course. I once attended an entire evening of Russian death scenes (now that’s entertainment!) sung by the legendary Bulgarian bass Boris Christoff. These days it would probably be packaged as Glum Boys.

But Terfel is now far more than a singer. He’s a national institution, at least in the land of his fathers. The capacity crowd that saw him launch this tour was just as tickled, one suspects, by his bilingual patter, his larking around and his whimsical props (a whip for the Te Deum from Tosca?) as by the ten numbers he actually sang. Especially as these were delivered between inconsequential orchestral and choral items (Sinfonia Cymru and London Welsh Chorale under Gareth Jones), a mass rendition of Happy Birthday to You (in Welsh, naturally) to mark Terfel’s 44th birthday, and lengthy pauses that killed the momentum as effectively as Sweeney Todd’s razor (another prop) slit his customers’ throats.

Bittiness was the big drawback, because it stopped Terfel from working up a real froth of malevolence. It’s one thing to produce a moustache-twirling rendition of the jolly Whistle Aria from Boiti’s Mefistofele (replete with ear-piercing whistle from the Devil himself); quite another to conjure up the sulphuric swirls consuming Iago’s soul in a quick burst from Otello. And Terfel often seemed to be coasting. His Mack the Knife was as menacing as a milkshake.

Yet few singers today could put across Dulcamara’s celebrated sales pitch from L’elisir d’amore with so irresistible a combination of vocal heft and verbal clarity, or Mephistopheles’s drinking song from Gounod’s Faust with such Gallic glee. And the show did give us a teasing taste of roles that Terfel will probably never sing on stage. Unless there is a sudden enthusiasm for Gilbert and Sullivan in the world’s great opera houses, for instance, we won’t hear his brilliantly caricatured When the Night Wind Howls (from Ruddigore) in its proper context. Nor is he likely to sing It Ain’t Necessarily So in a production of Porgy and Bess — though in these days of multicultural opportunity you can’t be certain.

But where was his Don Giovanni? And his Wotan? I felt shortchanged. Aren’t they bad enough boys to qualify?

Tour continues tonight, Festival Hall, London; then Nottingham, Glasgow, Birmingham, Manchester and Newcastle. www.raymondgubbay.co.uk

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