Complex sentence: Formed in 1990, they were originally a trio of madrigal singers, their first album, "Madra" (1991), was entirely a cappella, with the songs all based on traditional English verse.
Split into simpler sentences: Formed in 1990, they were originally a trio of madrigal singers. Their first album, "Madra" (1991), was entirely a cappella, with the songs all based on traditional English verse.