THE PROMS / Vienna whirl: Robert Maycock on the Gustav Mahler Orchestra and BBC Scottish SO

THE latest of the season's procession of youth orchestras has the wrong name - it ought to be the Anton Bruckner Orchestra. As a superbly prepared match of players and music, Monday's concert was a peak Prom experience. The sound is quite different from the other pan-Continental band, the European Community Youth Orchestra; even though it no longer restricts membership to the former Habsburg countries, it is unmistakably a central European orchestra to the ear, with its warm-toned but unvolatile strings, its choir of woodwind and fervent brass and explosive timpani. It's a good answer to those pessimists who, because they listen to commercially mixed records instead of going to concerts, think all orchestras have started to play the same way.

Claudio Abbado guided the GMYO through Bruckner's Fifth Symphony with extraordinary vitality. Still, it seems, we only partly grasp the complex nature of this strange Austrian composer, a mystic working at the height of the Romantic era. Perhaps because of that mismatch of time and temperament we tend to hear his vast musical forms as slowed-down, solemn versions of the dramatic progress that marks out music by Beethoven or Wagner.

But if instead the symphonies just exist, as though out of time - if all those tortuous shifts of harmony are meant not to go doggedly from A to B but to end up where they started - then one can take a liberated attitude in performing them. What matters is to balance the masses of sound and their durations; not to adopt a ponderous pace for its own sake. Abbado generated a vigour that was new in my experience of Bruckner. The performance's wholeness seemed to come from judging the tempo changes and dynamics. Whatever the reason, the Fifth was no longer an odd one out among Bruckner's mature symphonies for its persistent restlessness, but rather a key to understanding that quality in the others.

In a rare genuine encore, the GMYO repeated half the finale, as though to say, 'You didn't believe your ears? It really is like that.' Before the interval they gave close, intense support to Dmitri Hvorostovsky in Shostakovich's subtle but low-profile orchestration of the Songs and Dances of Death by Mussorgsky - the baritone larger than life, while still addressing each listener intimately.

From the BBC Scottish Symphony Orchestra there had been a connoisseurs' concert on Thursday, given an extra dimension for radio listeners when David Nice absorbingly put the case for Prokofiev's original thoughts in the Seventh Symphony, only for Martyn Brabbins to conclude his Prom conducting debut with the revised 'Stalinist' happy ending. Or maybe not so happy, since the performance was responsive enough to suggest that, before the door briskly closed, the lights had been put out. Simple but not simplistic, the symphony was well paired with Dvorak's Cello Concerto, in which Sophie Rolland went from strength to strength, enlivening a ponderous orchestral start, playing the momentous melodies like a cellist's operatic arias and ending with generous expansiveness.

Judith Weir's music fitted the context well, too. Its friendly harmonies are more sophisticated than they sound, and the light scoring makes subtle interplays of lines crystal-clear. Music, Untangled doesn't give much away, expressively speaking, but its few short minutes intrigued and delighted. In the more demonstrative works the BBC SSO played with fire and precision, as though their life depended on it - as indeed it might.