The mbira is a centuries-old African melodic instrument.Westernized versions known as the kalimba or thumb piano have been popularized here by musicians like Taj Mahal and Earth, Wind & Fire. Yesterday afternoon at the Museum of African Art, Paul Berliner played authentic mbiras from Zimbabwe as he was taught by that country's master musicians. Berliner's one mbira sounded like a small combo of steel drums and banjos, producing a rich mix of competing rhythms and melodies.

Berliner lucidly explained both the instrument and his own introduction to it. Three to 50 black iron keys are clamped over a wooden sounding board and struck with the thumbs and index fingers. The mbira is propped inside a huge, hollow gourd that acts as a resonator. Usually one hand plays a three- or six-beat rhythm, while the other plays two- or four-beat phrases.

Berliner, a Boston native, was a jazz trumpeter before traveling to Zimbabwe in 1971 to study from mbira masters there. He succeeded in earning the title of gwenyambira (mbira player). Yesterday afternoon, he got a perspiring crowd in the museum's brick courtyard to stand up, sing two different African melodies, clap two different rhythms, and dance an African step as he yodeled, sang and improvised on the mbira. Thus he gave Americans a small glimpse into the musical ritual of a Zimbabwe village.

Berliner's concert inaugurated the museum's free Sunday concert series. The next concert, scheduled for July 13 at 2 p.m., will feature the Batukada or Brazilian street music of Sebastiano Biao.