It has been my experience that a turkey might respond differently to a call on any given day . What that bird likes today may scare him off the roost tomorrow. The next time he hears it he may do a death-run to get to you. Loud and aggressive calling at any pitch will scare more turkeys than it will attract. Soft calling will bring more call-shy birds to the gun for sure. One thing is for sure, there are no rule-books when it comes to turkey hunting . There are no set pitches , high or low , that will always work on a turkey. Young hen today , gobbler yelps tomorrow, old hen the next time out ..... As David said , confidence in your calling helps prevent mistakes in what you are offering up for that particular bird. Just when you think you have one figured out , he'll do something to prove you wrong . Patience , not over-calling and woodsmanship will kill more turkeys than any one particular pitch to any call. Out of the 127 mature Toms I have harvested , more than half were killed with woodsmanship and very soft calling . If you think you have a rule-book for turkeys , throw it away ! LOL !!! That's just my humble opinion . Good luck this Spring !