LENOX — Into the third week of its Tanglewood season, the Boston Symphony Orchestra has had its ups and downs amid the triple handicap of hot, humid weather, short rehearsal time and a revolving door of guest conductors.
Things may pick up when Andris Nelsons begins his first weekend of concerts on Friday. Meanwhile, Spanish conductor Juanjo Mena lit a fire under the orchestra and had it sounding in great shape in a pair of concerts Saturday night and yesterday afternoon.
One campus, two worlds: While the Festival of Contemporary Music was exploring the new in Ozawa Hall, the BSO was making the old sound new in the Shed.
When you want to program the Tchaikovsky Piano Concerto — and orchestras love to program it because audiences love to hear it — Garrick Ohlsson is the pianist to call. From thundering octaves at the start to thundering octaves at the finish, his performance on Saturday rolled from fire to lyricism and back.
The fireworks weren't all the pianist's. Mena, the chief conductor of the BBC Philharmonic in Manchester, England, had the BSO answering and leading Ohlsson in controlled frenzy. The orchestral sound was rich and blended, deep and feathery by turns. Some of the attacks went off like rockets.
Ohlsson is a human powerhouse at the keyboard but he could also take his time. Some of the long first movement all but dawdled, achieving poignancy amid the virtuoso stuff. The finale's Russian dance went into rhythmic over-drive. There's nothing new to be said about the Tchaikovsky concerto. All you can do is play it well.
Chopin's Waltz, Opus 64, No. 2, was an encore for the demonstrative audience.
De Falla's complete "The Three-cornered Hat," the last half of the Saturday program, bears no relationship whatever to Tchaikovsky's warhorse. It is a ballet, with whirling Spanish dances interspersed amid what, in concert form, can seem like filler.
Maybe it takes a Spanish conductor to make a glorious racket of this colorful music. Rafael Fruehbeck de Burgos used to do it with the BSO, and Mena duplicated the feat, producing rhythms that were, perhaps, even more slinky, sultry and seductive.
But seduction is only half the fun, because mockery of small-town ways — especially of the corregidor, or magistrate — is at the heart of the matter. Cuckoo calls and a snatch of Beethoven's Fifth spiced the satirical effects that Mena drew from the compliant orchestra. Raquel Lojendio sang the solo bits as the miller's wife.
Yesterday's concert lacked the high gloss and energy content of Saturday's, but it came with a reduced orchestra and pieces whose energies lay elsewhere. It was no less absorbing for that.
A rarity, Ginastera's "Variaciones concertantes," marking the 100th anniversary of the Argentinian composer's birth, opened the program. It had been performed in its entirety by the BSO only once before, in 1994. Where has it been hiding all these years?
It is, as the title suggests, a combination of variations and concerto for orchestra. Echoes of Argentinian folk music are present but what mainly came through in the compelling performance was a strain of darkness. BSO section leaders showed their expressive powers in the solos.
Mena was no less effective in Beethoven. He took a relaxed approach to the "Pastoral" Symphony, which rolled out as mellow and sunny as the July afternoon outside the Shed (but Beethoven's was the only thunderstorm).
Veronika Eberle, a German in her mid-20s, made her BSO debut in a facile solo performance of Mozart's Violin Concerto No. 4.
Sibelius can take a long time getting to where he's going in his symphonies. The performance of the Fifth under Andrew Davis on Friday night, with winds and brasses dominant, helped the Finnish master along but wound up in a journey to the land of rhetoric amid the Nordic mutterings and rumblings.
As the evening's soloist, Lisa Batiashvili seemed to struggle against the heat as she played the Dvorak Violin Concerto. The performance was patchy; the showy aspects came across more strongly than the lyrical and pastoral ones.
Batiashvili took a solo encore — an arrangement of the largo from Dvorak's "New World" Symphony — and used the occasion to speak in sympathy with the victims of the day's terrorist attack in Munich, her home. The plea was heartfelt but unamplified, leaving it audible for only the first few rows of the Shed.
Davis, the music director of the Lyric Opera of Chicago, opened the program with Vaughan Williams' Fantasia on a Theme by Thomas Tallis. The performance was more propulsive than you usually hear but carried the cathedral-like sonorities.