Music Stephen Johnson NYPO/MASUR Royal Festival Hall, London

London-based Strauss-lovers have been having a good time recently. Wolfgang Sawallisch's authoritative South Bank Strauss mini-series is still fresh in the memory, and on Sunday Andre Previn showed that he too can be masterly Straussian in the Four Last Songs and the monumental Alpine Symphony. And the previous Friday, Kurt Masur and the strings of the New York Philharmonic Orchestra took on another challenging Strauss work: Metamorphosen for 23 solo strings.

The challenge posed by Metamorphosen is unique. For a start, is it orchestral, or is it a chamber work? And can this highly charged, large-scale but very intimate work reveal its secrets in a space as large as the Royal Festival Hall? Perhaps it can, but in this performance it sounded strangely impenetrable. One problem is the work's seamless lyricism. The leading string players are allowed to rest, but the melodic lines are so long and so skilfully dovetailed that the singing hardly seems to stop until near the end. When a performance comes off, that's no problem; but when it doesn't, you can end up wondering after 20 minutes or so if Strauss is ever going to pause for breath.

In Masur's performance, the onward sweep was relentless, lacking persuasive flexibility until the final pages and Strauss's revelatory quotation from the Funeral March of Beethoven's Eroica Symphony. Drive is important, but when the driver's eyes are fixed so obsessively on the road ahead it's hard to relax and enjoy the scenery.

But when it came to the performance of the Eroica itself, Masur's balance of forward drive and flexibility seemed just right. The first movement was compelling, but not tyrannically so. Here the phrases did sing and the rhythms danced. The tread in the Funeral March was measured, and not in a way that inhibited expression. To these English ears at least, the vibrato of some of the wind players was a little startling at times (especially the first flute and bassoon), but it could also be surprisingly seductive - notably the first horn, whose warm, fat sound and clear articulation in the scherzo's "hunting" trio section was the most memorable moment in the whole performance. It was an Eroica that held the attention, certainly, but as for emotional uplift - there opinions may be more divided.