In 1981 he became the vocalist in the NWoBHM band PERSIAN RISK ("Calling For You", “Ridin High”, "Rise Up"). 1984 PERSIAN RISK toured with MOTÖRHEAD throughout the UK.
At this point he received an offer to join GEEZER BUTLER (BLACK SABBATH) as lead singer in his solo project. The collaboration lasted from 1986 to 1988.
In 1990 Carl formed the band GHOST with ex-UFO and WASTED guitarist Paul Chapman.
From 1999 to 2002 Carl became the lead singer of the Swiss Hard rock band KROKUS ("ROUND 13").
2006 Carl joined up with DEEP PURPLE'S keyboardist Don Airey for his solo project "DON AIREY AND FRIENDS" and has co-written with Don ever since ("A LIGHT IN THE SKY", "ALL OUT", "KEYED UP", "ONE OF A KIND").
In 2009 Carl wrote his first solo album "MIND DOCTOR".
Later on Carl put a brand new PERSIAN RISK together and came up with the albums "ONCE A KING" in 2012 and "WHO AM I" in 2014.
Since 2015 Carl is the new singer for the legendary rock band NAZARETH after founding member Dan McCafferty had to retire due to illness. In 2018 the band has recorded Nazareth's latest studio album "TATTOOED ON MY BRAIN" (song credits include "NEVER DANCE WITH THE DEVIL", "CHANGE", "STATE OF EMERGENCY", "SILENT SYMPHONY", "DON'T THROW YOUR LOVE AWAY").
In 2021 Carl's new solo album "ELECTRIC EYE" will be released.