Max Carl Gronenthal is an American rock singer, keyboardist, guitarist and songwriter. He is the co-lead singer of the classic rock band Grand Funk Railroad. In addition, he spent several years as the keyboardist and lead singer for the southern rock band 38 Special. Carl is known for having co-written and sung lead vocals on 38 Special's hit song, "Second Chance" (1989).

Marcella Levy, known professionally as Marcy Levy and Marcella Detroit, is an American singer, songwriter, and guitarist. She co-wrote the 1977 Eric Clapton hit "Lay Down Sally" and released her debut studio album Marcella in 1982. She joined Shakespears Sister in 1988 with ex-Bananarama member Siobhan Fahey. Their first two studio albums, Sacred Heart (1989), and Hormonally Yours (1992), both reached the top 10 of the UK Albums Chart. Detroit sang the lead vocals on their biggest hit, "Stay", which spent eight consecutive weeks at number one on the UK Singles Chart in 1992. Detroit left the band in 1993 and had a UK top 20 hit with "I Believe" in 1994. She formed the Marcy Levy Band in 2002, and finished third in the 2010 ITV series Popstar to Operastar.