This snazzy Downtown music club consists of three parts: the Mainstage, an intimate performance space in the former site of the old Embassy Theatre, where national jazz acts play constantly and dinner theater service is provided by the wildly popular Wild Ginger restaurant; the Musicquarium, a side bar that books its own jazz acts, where patrons can watch tropical fish keep the beat in a 1,900-gallon aquarium that covers one wall; and sleek, glass-enclosed private suites with individual sound systems.