All music is new. The lullaby sung nightly reveals new shades and flights; the almost automatic encore piece astonishes as it turns thoughtful and complex.

The new is what makes music necessary. That thought was behind the baroque big band Tempesta di Mare's Friday performance of American premieres of four 250-year-old works by Johann Friedrich Fasch.

The ensemble's leaders, Gwyn Roberts and Richard Stone, have been pressing research into Fasch's output and are on the way to resuscitating music enough for several more programs. Fasch was a contemporary - and neighbor - of Bach and Handel, and lived and worked near Dresden. He might have weathered the centuries better had World War II not damaged the library where much of his music was archived.

The rescue of the three concertos and a suite in F played Friday at Swarthmore's Trinity Episcopal Church involved, among others, Canadian scholar Barbara Reul, who devised computer enhancements to realize the truth behind water-damaged sheets of notes mostly devoid of staff lines.

Fasch was no Bach, no Handel. He found another colorful path, skirting the dazzling formalities of Bach and testing terse ideas of melody in building his strongly colored works. Neither Bach nor Handel could have imagined the bold flourishes Fasch splashed on his players. Neither would have so obviously catered to his listeners. Fasch aimed to please - both listeners and instrumentalists.

Tempesta shaped the program's order from the plain to the fancy, ending with the

Concerto in D

. That work, with its big floor plan, extravagant writing for winds, and dashing violin solos, seemed to predict the glories of the late 18th century. Here was the Mozart orchestra in baroque scale and timbre. Mozart didn't get to use a theorbo, nor did he ever write a chain of rising and falling trills for two natural horns. Included in this three-movement piece were extended flute duets, oboe duets, internal chamber groups with bassoon, all ending with a catchy motif that Haydn might have imagined.

The only minor-key piece, and the one that seemed to have truly serious things in mind, was the tantalizing

Concerto in d

. Fasch was a flatterer and an optimist, but to hear this full orchestra musing was to hear a composer seeking a wider vision. Flutes, oboes and bassoons shaded the string writing, moving in lines that sounded operatic.

The

Concerto in F

and

Suite in F

introduced Fasch without showing just how broad his horizons might be. The ensemble is working a rich vein, promising much more old (new) music.