Rebel hog is right. You can spook 'em fast if you hit the wrong note. I found a low continuos grunt while walking to the stand is an excellent cover sound. I've actually walked right up on them like that, but they blow out as soon as they see you stand tall on 2 legs not 4. The other is the feeding sounds. They do like to come in when it sounds like other pigs are getting some food and they're missing out.!