There's always an odd kind of nervous tension at the beginning of a museum show. The hushed and painfully reverent atmosphere of the museum carries over into the amphitheater. The audience doesn't know what to do with themselves -- museum audiences would applaud a grocery list if you read it to them.

Thankfully the soulful Deva Mahal (Taj's daughter) and Stephanie Brown of Fredericks Brown reminded us all that we were there to enjoy ourselves when the two opened last night's show.

Deva Mahal has a powerful voice -- the kind of attention-grabbing power that, if you've forgotten, reminds you that some human beings have gifts reserved for very few. Armed only with a tamborine and Brown's minimalist organ and bass accompaniment, Deva warmed the room with her gospel and blues vocals. MIM's theater is a perfect space to showcase Deva's voice, and Fredericks Brown wisely took advantage of it.

South African activist and musician Vusi Mahlasela followed Brown, not an enviable position, with a two-song acoustic set. It's difficult to describe Mahlasela's emotional range. That is to say, his range is wider than ours. Light years wider. Mahlasela opened with "The Beauty of Our Land," which he sang in Zulu. This reviewer obviously didn't understand a word, but, as is true of most music, the emotional and dramatic arc of the song's sound was impossible to misunderstand.

Mahlasela explained afterward that "The Beauty of Our Land" was not only about South Africa's majesty, but also a political statement about apartheid's ugly history. Vusi sings with humility and honesty about human forgiveness, an important tenet of his Ubuntu philosophy. His South African blues preaches empathy, an emotion not commonly associated with Western blues.

When Taj Mahal climbed on stage, his opener seemed as much homage to BB King as it did homage to Thelonious Monk. Mahal has a very democratic approach to the blues -- there's a little bit of everything in there: zydeco, calypso, jazz . . . He sheepishly called the opener, "The 'Uh Huh' Blues."

Even though "Uh Huh" was rooted in traditional twelve-bar blues, the song was at times atonal and uncomfortably syncopated. Uncomfortable in a good way. Thelonious Monk is famous for this -- his piano playing focused on the silence between the notes as much as it did on the sound the notes actually made. Very cool.

Mahal demonstrated his range when he sang some calypso and then the country blues song "Fishin' Blues." As he changed styles, he moved from guitar to guitar, picking up a steel to strum during a duet with his daughter. A banjo also made an appearance, but the drum kit drowned out most of the instrument's nuance.

Last night's show was quick, but it didn't seem rushed. The arrangement was as democratic as Mahal's blues; Vusi, Deva and Stephanie all returned for an encore, generously sending us on our way.

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