Karl has been an in-demand session guitarist for the past 20 years, and in that time has recorded, gigged and toured with many acclaimed international artists, including Clannad, Gavin Friday, Brian Kennedy, Lesley Garrett, The Irish Tenors and Briana Corrigan (The Beautiful South), among others.

His TV work has seen him perform as a backing musician with Elton John, Westlife, Olly Murs, Sugababes, Enrique Iglesias, Katie Melua, LeAnn Rimes, Natasha Bedingfield, Rodney Crowell, Andrea Corr, Steve Earle, Deacon Blue, Cliff Richard, Russell Watson, Sharon Shannon and Andrea Bocelli.

Karl regularly acts as a theatre guitarist, performing in the pit for amateur and professional theatre production companies around the country, along with regular sessions with the RTE Concert Orchestra.