Sparta-based singer/songwriters Rich Mattson and Germaine Gemberling will perform songs from throughout their recording career, talk about their songwriting process and share stories about their life as musicians during the second installment of the Sacred Heart Music Center Songwriters/Storytellers Series. Minnesota arts advocate Karen Sunderman will host. Rich Mattson is a musician/songwriter and producer/engineer living in Sparta, Minnesota. He began performing in 1980 at the age of 13, and took up songwriting shortly after that. Since then he has led and played…