A Friday afternoon at the symphony has an almost giddy feel to it. The weekend hasn't actually begun, so there is no gravitas of a nighttime excursion, and those of us in the audience who aren't retirees have that slightly adolescent pleasure of slipping away from the work week just a little early. At the Boston Synphony Orchestra concert in Boston Feb. 15 at 1:30 p.m., I even overheard one pretty, middle-aged woman confess to her companion that she hoped this was good because she had rescheduled a lunch meeting for it. She didn't regret her choice. The first note of the Sibelius violin concerto was dissonant, and when Vadim Repin played it, the fate of the world hung on that one note, held just too long for comfort before blessedly collapsing into the tonic. The first movement moaned and wept, the brilliant accompaniment heightening the emotion pouring from the soloist.

The Adagio di molto melted on the ear like fine chocolate does on the tongue. Sibelius, a failed professional violinist, threw into this second movement all he wished he could have expressed on his own instrument. The swelling and falling waves of music are wonderful on recording but in a concert hall were nothing less than mesmerizing.

I was actually worried as Repin touched up his tuning before the third movement, a leaping, frenetically and forcefully optimistic romp. The richness of the first two movements could be ruined, I thought, if the same heady melancholy couldn't be converted to rollicking motion. But from the start, the orchestra and soloist together launched into an almost flailing display of sound. I am glad Repin's performance was pristine, but not flawless; the fiendishly difficult piece would have been inaccrochable, as Gertrude Stein put it, without a few intonation errors in those double stops. As it were, the eminently inconsequential inconsistencies almost kept the concerto's emotion in check through the last shining note. I was and am floored by the power of Repin's playing and the beauty of the piece.

After insistent cheers and applause, though, Repin had more to say. He spoke for a moment to the concertmistress, who passed along instructions to the first violins, and they began a simple pizzicato two-chord progression. Repin instructed the seconds and violas to join in and added the low strings with plucked bass notes. And then he played a Fantasia on the Theme of "Oh Yes, We Have No Bananas." That's right. He followed a masterwork of concerto composition with a gallivanting and mindblowingly virtuosic display of violin technique based on "Oh Yes, We Have No Bananas." I think I'm in love.

Shostakovich's intense Symphony No. 4 was a wonderful end to this staggering concert. Guest conductor Mark Elder spoke briefly in his clipped British accent about Shostakovich's troubles while writing this piece: The composer was in such danger from being taken away by Stalin's KGB for his dissonant, non-proletarian music that he kept a small suitcase of essentials by the door should agents come for him in the night. All that fear and fury that the youthful Shostakovich must have felt boiled up through this symphony, which had not been heard in Boston for 30 years. When, in the fourth movement, the symphony finally rested in a major key, the tension in the hall thinned palpably; the driving chords bursting from the enormous orchestra had actually made my heart rate increase, such was their power. In fact, it is hard to put into words the effect of the Boston Symphony Orchestra's performance of the Symphony No. 4. All that can be said is that the talent of the musicians combined with the sheer force of the composition created, just for an hour, a facsimile of the dread that pervaded Shostakovich and others in Soviet Russia, all within the concert hall.