Enough world music devotees showed up at Johnny D's on a school night to make the performance by Zimbabwe's Thomas Mapfumo worthwhile for both artist and club. Tuesday night, a dedicated crowd grooved to midtempo rhythms anchored by the mbira, the southern African ''thumb piano" built into a gourd, for two solid sets that stretched into the night.
The show was a small triumph over adversity, as it had been rescheduled twice, in part due to Mapfumo's car breaking down somewhere on the cross-country drive from his Oregon home. Visa difficulties depleted his band, the Blacks Unlimited. The improvised lineup included a stand-in drummer, a second mbira player from Haiti, and local African music maven Banning Eyre, a longtime Mapfumo friend, on guitar.