I am still debating on weather to buy a DF with the larger 12 inch coil. I read plus and minuses from the Excal 2 that I own. Will the DF create loud sounds of deep targets that are below 24". I don't know if I want to dig any deeper or even close that in the ocean as the sand will fill the hole faster than I can dug. Can you tune this machine to get less sensitive and spot targets within the 18" and above range?