Hi everyone this Darryl author of "thirty inches", To Willwee I new there would be naysayers but please don't insult me by calling me a liar, and yes the deepest silver quarter I've ever found was correctly I.D. by my conductivity scale on my GTI 2500 in pinpoint with no audio and YES IT WAS ABOUT THIRTY INCHES! I have dug well over one million holes in my life and I dig thousands of slight chirps no others would bother with. I have dug thousands of coins in the one to two foot range! I have taught my partners and my friend using an SE recovered two Quarters, one a seated in AU and a barber in AU at approxiamately two feet just this spring. At one county fairgrounds in the parking lot we discovered the foundation of the old armory by accident, we found many great targets so I fished in this area and strangely I found most good targets around 10 to 14 inches and then a layer of pulltabs deeper then that, thats right pulltabs deeper than fourteen inches! Now these depths are only achieved in perfect soil conditions there are places I detect where four inches are the maximum. Have you expirimented with your pinpoint on your 2500 as I suggested? if so you will discover it will ID conductivity well past it's audio range. As far as depth you must run a defective 2500 because my friends and I have tested the SE and the 2500 under many different senerios and found them to be practicly identical on depth, although as I stated the GTI pinpoint is magical if you have the talent to use it, by the way what is your deepest coin of your life? My mother always said " if you have nothing positive to say say nothing at all". Willee I hope you learn to find the deep ones too, good luck, Darryl.