The easiest way to sound better is to get a call that is tuned for you, not just thrown together. there are a few calls that come out of the box pretty good, but others need to be tuned to your liking. for a doble cluck it is best to master your high cluck, and your low cluck and then put them together, and speed it up through practice. to moan i just make a GUHHHHHHHH sound, and i bring it from deep down in my gut. and for a come back i just use sort of an EEAAWWW, and i throw in a little voice inflection. i hoped that made sense i havent really tried to explain it before