Two Early Music Now concerts this season diverted into folk music, a broader definition of what comprises "early music." And why not? Last fall Trio Mediaeval presented a program of Nordic folk songs. Music from the opposite end of Europe was featured in a concert Saturday night by Kitka at the Basilica of St. Josaphat.

Kitka, a women's vocal ensemble based in San Francisco, specializes in music from southeastern Europe, particularly from Bulgaria. Music of this Balkan region for women's voices has a distinctive style and sound, at first startling to those unaccustomed to it. A chest voice belt has been cultivated to high art. The sound is both rambunctious and subtle. Kitka's tone is pure, and tuning is impeccable. Its ensemble and phrasing is highly evolved.

There is strange wonder in the stunning arrangements of richly asymmetrical folk music Kitka performed. Slowly emerging harmonies seldom headed into expected territory. The seven-voice ensemble performed primarily in what I assumed to be Bulgarian. Even with brief paraphrases in the program about the meaning of the lyrics for each piece, this music evoked exotic mysteries.

A soloist, Tzvetanka Varimezova, joined the ensemble on several numbers. Her voice is both sweet and forthright. American ears are not accustomed to the agile, complex ornamentation of this style, which at its best organically creates stirring emotion. Periodically Ivan Varimezov played bravura solos on the gajda, a Balkan bagpipe, and also accompanied some of the singing. It was immediately clear that the ornamented singing style is closely related to the similar musical lines heard on the gajda. Milwaukee Choral Artists, a women's chorus, joined Kitka on a few pieces.

The Basilica's tricky acoustics are flattering to unaccompanied small vocal ensembles such as this. My only complaint about the program was that there was too much of a good thing. The 24 pieces could have been cut down by a few to create a better paced concert. Was I the only one who got confused following along in the program and figuring out which piece was being sung in the second half?