quiet mode

I just made a super deal on a prizm2....Have one ? about new detectors..are they made to operate quiet for the first inch or so below the coil....I'm running the discrimination on lowest number...I've only hunted about 3 hrs with this detector but I'm shocked how deep my targets are.My two deepest targets have been at 6 and 7 inches...one a pull tab......another a silver $.25 at 7ins.....which doesn't sound all that deep except it was dead center of plug on edge...got a real nice sound when i clicked over to the all metal mode....I've been carrying a rule to measure with still working on figuring out sounds.....helps me to know how deep goodies are.I'm pleased my finds so far 9-1cent....7 10 cent one was a 1954 silver....5 -25 cent....one 1964 silver....plus a token that has on it no cash value....on the back is an eagle with a shield....when I figure out how to post photo I'll post token...thanks all..George