I have had reasonable early season success with calling. I usually will use buck contact grunt calls (not the pig like grunt they use during tracking or chasing does) I will occationally use light sparring sounds with the rattling antlers. Even doe bleats will help draw in a buck.
The best early season tactic I can offer is get on the most productive white oak ridge where the acorns are falling like rain and sit tight. This seems to be the best early season food source I have hunted. These ridges with oaks are often near a bedding area and bucks feel comfy coming out and eating during daylight hours. Next best place is a watering hole. They will come to one of these just about any time of the day. Third, stay smart in the early season and don't get careless with scent control. Scent lok up, use odor eliminators, shower before each hunt, and watch the wind. The last thing you want to do is ruin your stand sites before they get good.............Hope that helps