Prague’s classical music community is walking a little taller and prouder this week. After a series of disappointments from high-profile early music groups in this year’s Prague Spring festival, the city’s own Collegium 1704 stepped up on Saturday night with an 18th century opera program that offered an inspirational reminder of how period music can and should be played.

Founded by harpsichordist and conductor Václav Luks in 2005, the ensemble breathed new life into Bohemian Baroque composers like Jan Dismas Zelenka and Antonín Reichenauer before expanding into the operatic repertoire. Its “Baroque Opera Stars” series of concerts at the Rudolfinum the past two seasons have nearly all been sellouts, featuring singers like Sonia Prina, Topi Lehtipuu and Martina Janková. Current opera engagements include a production of Purcell’s King Arthur in Dresden, Josef Mysliveček’s L’Olimpiade in Prague and a critically acclaimed production of Handel’s Rinaldo that is concluding its fifth successful season at the National Theater in Prague this month.

The Saturday concert was mostly Mozart and Haydn, with nods to Mysliveček, Leopold Koželuh and Luigi Cherubini. Another Prague favorite joined the ensemble – soprano Simona Houda Šaturová, a regular in National Theater productions. The program, built around a theme of women in distress, included a sampling of one of her current roles, Konstanze in The Abduction from the Seraglio.

What characterizes and distinguishes Collegium 1704 performances is the ensemble’s absolute fidelity to the music – Luks often goes to original manuscripts to research the composer’s intent – coupled with an enthusiastic playing style that makes the sound vibrant and fresh without slipping into modern. Luks is a craftsman who carefully sculpts and balances every note and phrase, typically working from the floor rather than a podium, which better accommodates his athletic conducting style. In every sense of the word, he is inside the music.

Luks set the pace and tone for Saturday’s performance with a high-energy opener, Haydn’s overture to L’anima del filosofo ossia Orfeo ed Euridice. Up-tempo and pulsing with the dynamics of an expanded 35-piece group, it was almost electric. The effect was such that Houda Šaturová strode onstage applauding along with the audience, then slipped into character immediately for Haydn’s “Berenice, che fai?” She has a round, tender voice that can be dramatic without any edges, or lyrical with emotional heft – or both. Her coloratura was not very sharp in this aria, but her passion matched the orchestra’s intensity, and Luks did a fine job providing graceful support to her phrasing and tempo.

Other musical selections in the first half gave the ensemble a chance to show its skill at creating effervescent melodies, as in Koželuch’s Sinfonia in G minor, and its authoritative command of Mozart with a ringing, portentous version of the overture to Idomeneo. Houda Šaturová’s vocals floated elegantly over the music in Elettra’s “Idol mio” aria from Idomeneo, and her coloratura was better in a Cleonice recitative and aria from Mysliveček’s Demetrio. In the latter she seemed to propel the orchestra’s rhythms, rather than the other way around, and a concluding series of glittering high notes drew sustained applause even from Luks and his players.

The ensemble brought different shadings to Mozart in the second half, with a fine balance of boisterous and stately elements in two selections of ballet music from Idomeneo – the first beguiling in its melodic sweep, the second witty and fun with fast-paced changes of tempo and phrasing.  Houda Šaturová brought some dark tones and deep emotions to Mozart’s “Misera, dove son?” and a dramatic sound and character bordering on anguish to the title character’s “Dei tuol figli la madre” aria from Cherubini’s Medea. But she outdid herself in the finale, a bravura performance of Konstanze’s “Martern aller Arten” from Seraglio. Working the higher register with finesse and finally hitting her stride in the coloratura passages, she captivated the audience with an emotional outpouring that left her leaning on a music stand for support after she finished.

If it was a bit over the top, no one cared. After a surprisingly tired performance by the Hilliard Ensemble the previous night, and an inexplicably anemic performance by the Freiburger Barockorchester earlier in the festival, the energy was rejuvenating. Les Arts Florissants gave a definitive account of Monteverdi’s Seventh Book of Madrigals on the same stage a week earlier, but when countertenor Andreas Scholl fell ill, forcing a cancellation of his performance with Accademia Bizantina, it looked like period music fans would leave Prague Spring without much to remember this year. In the waning days of the festival, a Prague ensemble with its own style and ideas changed all that.