Using one of the digital voice recorders (Olympus) load your human voice to the computer via the MIC located on Accessories. Then download them to a drive then to your caller like many of the Foxpro callers. Lip Squeals, Rabbit Distress, Coyote Barks Howl, Barks, Puppy Whines, cat, turkey yelps, etc can out smart many a predator... Kind of hard for a person to do 10 to 20 minutes of rabbit squalling with the human voice.. However placed on the right caller the calling sequence can be endless..