tUnE-yArDs is Merrill Garbus. She writes the songs, which frequently consist of musical riffs broken into pieces and shards, glued together with an organizing rhythm. She provides most of the multi-layered vocals, much of the percussion, as well as various keyboards, ukele and other instruments and objects. Working with bassist Nate Brenner and occasionally a few other singers and instrumentalists, Garbus gives electrifying performances that showcase her remarkably flexible singing voice. In her ability to create music that sounds at once invitingly familiar and disorientingly new, Garbus is the real thing — an original artist.