Kveldssanger and Nattens Madrigal are the second and third studio albums by Norwegian black metal band Ulver. Kveldssanger is an acoustic album with clean vocals and folk elements, while Nattens Madrigal is a conceptual album with a theme of lycanthropy and the dark side of human nature. Both albums are part of the 'black metal trilogy' based on Norwegian folklore. Kveldssanger features acoustic guitars, violin, and flute, while Nattens Madrigal is a raw and melodic black metal album with occasional acoustic elements. The album was recorded in the forest to capture the spirit of the music.