Opera Casalinga, Montgomery County's fledgling professional opera company, brought its season to a thoroughly impertinent close last weekend with Tom Johnson's delightful operatic spoof. "The Four Nore Opera." In a production as saucy as the opera, which truly relies on only four notes, the company had a splendid time cavorting about the stage at Rockville's Jewish Community Center, turning upside down all the grand conventions upon which opera relies. Indeed, one hopes that the company will consider making the work a perennial affair, offering it as a musicl purgative every few years to restore the health of the operatic tradition.

In the opera a soprano, a contralto, a tenor, a baritone and, occasionally, a bass pursue exaggerated moments of love and adventure while declaiming a text that reduces operatic structure to absurdity. the entire cast caught just the right approach both musically and dramatically, using a broad style without sliding into excesses. Baritone Michael Pinkerton, in addition to possessing a rich and free sound, presented a comic face of dazzling mobility that was an unceasing visual treat. Soprano Naomi Frenkel's gifts were particularly evident in an amusing paradoy of voacal and instruments imitative exchanges that found her fluttering with fear as the piano echoed her notes. Tenor John Day, though his voice was somewhat tight, projected his heroic stance with flare. Contralto Cynthia Beitmen showed a sharp sense of comic timing, and bass Wayne Jones made his few entrances memorable. Terry Glaser's staging was fresh and imaginative, ably complemented by music director Adaure McConnells sure hand.

It was an evening that no opera lover -- and no opera foe -- should have missed.