This is likely not going to mean much to most people here, being very much a French/Québec phenomenon, but I have to mention it.
This band as a whole, and especially his voice, meant a lot to me and my wife, particularly in light of her current fight.
Anytime we go anywhere vaguely long distance, we always start by putting on their album, L'expédition, and everything's always gone well (the ONE time we didn't, we totaled the fuckin' car, so, yeah). So this loss hits very hard.
In a larger sense, this is the loss of an absolute ICON in the Québec music scene. He'll be sorely missed, and I can't imagine the band going on after this.
Bon voyage, Karl. Repose-toi bien, maintenant.