First of all, turn Tracking ON. There is no earthly reason not to.
Where is your Threshold set? It should be audible, but minimally so. With good phones somewhere around 4 should be about right.
If you're shooting for max depth, ditch the filters and go All Metal.
Other than that, the 5x10" coil is depth limited by it's width.
Even under the best of circumstances it isn't much good on targets more than about 6" deep unless they're HUGE
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L.H.,You should include the LENGTH (9") in that
[size=large]generalization[/size]......
The approximate max (consistent audio related) detection depth of the 9" by 5" elliptical coil, is 6.25 times the coin's diameter (in inches)...
poor.ground-conditions will invoke limitations to that depth approximation......... metalpopper.
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