I've had my AT pro for a while, using and learning as I find lots of items. I was cleaning off the dirt and sand and realized I haven't used the headphones yet. So I attached them, turned on the AT pro and hit my backyard. The sounds were clear and varied. I even had to turn the volume knob down. I heard multiple signals within a few inches. Dug up 2 old matchbox cars, 1 wheatie and a depression era lipstick case, all at 2-4 inches. I am definitely hearing more signals and swinging the coil better. I going back to a hot spot tomorrow because it rained yesterday. Peace