Last week they were inaugurating their new concert hall in St Petersburg. This week they are continuing the Shostakovich cycle at the Barbican with six major symphonies. In between there was the minor matter of Wagner's Ring at the Wales Millennium Centre in Cardiff. The Mariinsky Theatre Orchestra and Chorus, and especially their general director Valery Gergiev, are seemingly inexhaustible.

Nor was there the slightest sign of flagging in either of the two Shostakovich symphonies, Nos 6 and 13 (Babi Yar), in last night's Barbican concert. The sombre colouring of the latter (with Sergey Alexashkin a suitably sepulchral bass soloist) was sustained with a searing intensity that was almost unbearable. Even the Scherzo was exploited for its savage, black humour.

But these players are capable of rapt stillness as well as whipcrack precision: the end of Babi Yar was followed by a long, deep silence.

The Ring/Mariinsky Opera
Millennium Centre, Cardiff
***
The Ring was one of the year's hottest tickets - sold out within hours of going on sale in March - but only the most loyal of Kirov acolytes could pretend that it delivered all it promised. It is, to be sure, a monumental achievement in itself to tour Wagner's great tetralogy to several continents and George Tsypin's primitivist sets powerfully relocate the Nordic myths in an imaginary terrain closer to Asia and the Russian steppes.

Giant figures, sometimes topped by death skulls, sometimes by humanoid heads, sometimes headless, lour over the action, while manikin figures in turn suggest Russian dolls, burial urns, a miniature terracotta army and embryos, with costumes by Tatiana Noginova drawing on Tartar, Mayan and Egyptian references as well as Russian.

The climactic Immolation Scene movingly visualises the progression from a barbaric, god-centred world order to a new humanistic era. But sadly there is little evidence of any other intellectual content over the course of the 14 hours. Worse still, there is no spark of theatricality to animate the shell of Tsypin's design concept.

Some of the lighting in the first two operas was still rehearsal lighting and neither orchestral playing nor singing evinced the kind of detailed, text-responsive preparation that these works demand.

Gergiev and his forces are the most remarkable ambassadors for Russian music-making. Sometimes they fall below their own impressively high standards. But you have to admire a company that can even aspire to those heights in the modern era while playing away from home.

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