15" coil

I have the 15" coil for my Nox 800. I have not really dug many deep signals due to the summer and early fall drought in the south. Now rains have come and the dirt is now moist. Question on faint signals. Will a silver dime laying flat sound pretty much the same at 11" deep as say 6" deep...

I read that a the 15" coil for the equinox is coming. Anyone got any ideas on what to expect? When I got my NEL Thunder it really didn't do that much for my AT Pro. It was real sensitive to being bumped by any small scrub brush. But to be fair to NEL I didn't hunt many open fields so it...