The Trio Sonatas of Bach are not, despite the implication in the title, scored for three instruments. They are actually solo works for organ, with three subjects intertwined in one piece. It sounds technically challenging because it is. This is music of wonderful complexity and richness, but it’s rarely performed live. Taking a cue from that misleading title, Tempesta di Mare will present all six of the Trio Sonatas reconfigured in a variety of chamber-music combinations, ranging from lute and harpsichord to full ensemble. Sharing the burden may make the music a bit easier to present, but even the solo lines are daunting. Bach, to the eternal delight of music lovers, showed no mercy to his performers.

Sat., Feb. 2, 8 p.m., Arch Street Meeting House, 320 Arch St., and Sun., Feb. 3, 4 p.m., Presbyterian Church of Chestnut Hill, 8855 Germantown Ave.; $20-$40, 215-755-8776, tempestadimare.org.