New York ethno-fusion collective TriBeCaStan will perform a special acoustic concert on Friday, August 2^nd at the Rubin Museum, as part of the museum's ongoing Harlem in the Himalayas Concert.   The special all-acoustic performance, inspired by the Rubin's collection of ethnic art, is being designed specifically for the museum's intimate space.  The concert also promises a preview of the band's fourth album, NEW SONGS FROM THE OLD COUNTRY, which is due for release on Evergree