I have called coyotes in with johnny stewart calls and primo's hot dog and little dog,you can call them in with any call if your setup is good and the coyote is willing.You should concentrate on your set,the wind direction with relation to where the coyotes are coming from to get to you,and scent control.I have called them in with turkey calls while turkey hunting,the sound you make just needs to sound in distress the realism isn't as important as being where they can hear you and not see you until it's to late.I use a foxpro electronic caller most of the time anymore,because of the ability to get the sound away from my location and the ability to make a lot more sounds than I can by mouth,but a mouth calll is just as effective and you don't have to be a world champion caller to call in predators just hunt them every chance you get and you will score on a lot of animals over time and figure out what works best in your area.GOOD LUCK!!