The artsy hard rock group Pavlov's Dog spanned progressive music and heavy metal in much the same way that Rush did in its early days. Also like Rush, Pavlov's Dog had a singer, David Surkamp, whose distinctive high-pitched voice was the group's take-it-or-leave-it factor. Outside of a small cult following, most folks chose to leave it, but over the decades Pavlov's Dog has remained a popular find for fans of the obscure end of American arena rock.