It is so good to see the occasional matinee performances by the CBSO attracting a very large audience, and today's concert was packed to the rafters. And it wasn't just the usual demographic of, shall we say, the more gentile of afternoon concert-goers; the concert attracted large school parties, together with college & university students taking advantage of both their "free" Wednesday afternoons and much reduced ticket prices for students.

The choice of programme also made way for two relative youngsters as today's main performers: American conductor Ryan Bancroft (b.1989, Los Angeles) and Clarinettist Oliver Janes, who, at just 29, has already banked eight years as Principal Clarinet with the CBSO (2014-2022).

It is with the playing of Oliver Janes we consider first, because, in many ways, Oliver's performance of Mozart's very well-known and much-loved Clarinet Concerto totally stole the show. Indeed, this was a stunning and revelatory performance of the Mozart, which made one listen with entirely new ears.

Oliver Janes's attention to detail is superlative, be it: the elegance of phrasing; an exquisite beauty of tone (particularly in the lower register); a deftness of touch & utter precision in the more rhythmically gymnastic (and highly challenging) sections; the wonderful manipulation of dynamics, plus; a unique sense of musical narrative, which allowed this work to jump off the page, engaging the listener in a wholly new kind of way.

For example, two things stood out: in the first movement there is a lovely passage where an almost operatic call and response duet takes place purely in the clarinet part, with deep, mellow melodies calling out from the lower register, answered in turn in the upper register. Quite magical. Second: in the slow movement, when Janes and the orchestra reprise the opening material, we don't think we have ever heard such a profound and deeply affecting use of pianissimo (pp); this was a pppp pianissimo - together with a pulling back of the tempo - for both soloist and orchestra: truly a sensational moment of total unanimity and musico-emotive empathy.

Given that this concerto was composed during the last few weeks and days of Mozart's tragically short life - and written in the same year as the Requiem - the meaning of Janes's interpretation was not lost on anyone - quite simply: exquisite playing. Also, in Janes and the CBSO you have players who don't just know how to play their instruments, but how to play the astonishing acoustics of Symphony Hall; almost as though the Hall is one large instrument in itself, which, of course, in the remarkable design of the building's architects, it is.

Kicking off the concert was The Chairman Dances by John Adams (b.1947). This is a great piece of contemporary American minimalism - some might say post-minimalism - and it is a work where an orchestra can really shine. It is also a piece where one cannot take one's eyes off the huge battery of percussion instruments, here played with incisive and exciting accuracy - again, another delight for the many children and young people in the audience.

The second half consisted of just one work, the Symphonic Dances by Sergei Rachmaninoff (1873-1943) written in America at the very end of the composer's life. This, too, is a bit of a showpiece for the orchestra - and indeed for the conductor. However, and there is no easy way of saying this: this is just not a very good piece of music, and in a concert with such an engaging first half this was a rather strange choice of programming.

These so-called Dances are a meandering thing, where any sense of dance never really takes off. There is, of course, a gorgeous solo for Alto Saxophone in the first movement, superbly played by Kyle Horch, and there are other such moments of interest in the overall orchestration. However, while this work has some showy orchestration, it is perhaps not the best choice to really satisfy an audience.

This is such a shame. After such a stunning first half the choice of this rather dreary Rachmaninoff in the second was a real downer, and one wondered what the many young people in the audience made of it? Also, there seemed to be a certain lack of edge, or the kind of crispness of playing we had experienced in the first half. With the huge forces of the CBSO assembled en masse why not give us a big Symphony - a Shostakovich or the such-like? Programming is such a fine art, and sometimes the need to balance a programme - and thus leave an audience feeling satisfied - is essential.