I apologise if this has already been covered, but I can find little about Karl, who seems to have been prolific having been a writer and producer for many acts
The Kavettes, Mel And Tim, Bull & The Matadors, Jackie Wilson, Jo Ann Garrett, Chicago Allstars, The Voice Masters, Gene Chandler etc.
He had a clear connection to Andrew Williams (Already have his story) and Carl Davis, but there appears to be little info on the Web.
He did one single himself (that I know of)
I guess there are Chicago experts on here who may know a little or a lot, but I think we need his story, if you can help please