Toms with hens in tow are not too interested in "potential" hens. They h ave the real thing. Other Tom's, however, can spur a reaction. When it becomes obvious they are not reacting to hen calls, I switch to Tom calls. Loud and raspy gobblerr yelps, fighting purrs, and gobbles. And the gobbles don't need to be perfect. I've called in birds with some lame imitations of a gobble on a mouth call. All they need to know is that there is competition in the area.