As the lead singer of Sigur Rós, Jon Thor Birgisson mewls epics in a made-up elfin language (called, with impossible preciousness, Hopelandic) over glacially moving orchestral passages and rock rendered as ambient whale song. For his solo project Jónsi, Birgisson often ups the tempos and even tasks his tongue with singing in English, and the results are surprising and immensely satisfying, whatever your attachment to his main gig. "Animal Arithmetic" is a thrilling charge, percussion thundering like a stampeding herd, Birgisson running down a litany of vivid sensations, concluding, "We should all be (oh!) alive!" Elsewhere, his debut album, Go, approaches the grander sweep and slower pace of Sigur Rós, but it's fair to say this is his "pop" record, and it's an absolutely outstanding one. by Eric Grandy