Behind the Technicolor masks worn by Peruvian tropical bass duo Dengue Dengue Dengue are Felipe Salmon and Rafael Periera. The tropical sonic warriors bridge continental divides by uniting the Danelectro-fueled surf rock of sun-bleached 1970s California with psychedelic rock, Caribbean dancehall, German techno, and Amazonian cumbia on the new “Siete Raíces.” It’s a fusion borne of conquistadors, imperialists, and spice traders melding African and Asian rhythms with the tribal Afro-Peruvian sounds of the Andes.