Texas-kid, You can certainly knock out all lower conductors, and simply pass tabs and foil if you want to

But I sense you're asking this, in terms of not-wanting to miss gold jewelry, right? Which shares the same conductive ranges as aluminum for the most part.
If so, then you'll have no shortage of people telling you that you must dig aluminum till your arms fall off, and never pass tabs "lest you miss a gold ring". As if that's the recipe, plain and simple, to digging gold rings right? WRONG!!
It's already a given that gold rings are almost always low conductors (unless you're talking some big fat mans honker ring). So to simply tell someone "dig all the tabs" as a recipe to finding gold rings, can be a lesson in insanity. I can think of blighted parks where you'll dig 5000 pieces of aluminum cr*p before you'll EVER get a gold ring. What the heck type of sense does that make ??
Thus the solution to the "gold ring" problem is not some sort of trying to figure out how to notch them out (ring enhancement programs), or fiddling with all such sounds, etc... No no no. The much BIGGER issue is WHERE you hunt. Because if gold rings are your goal, then what the h*ck are you hunting junky blighted parks .... to begin with? Instead hunt locations where the demographics are better and more conducive for jewelry losses, to begin with! Namely: swimming beaches. And let's face it, sand is much easier to dig in. Doh!
I've hunted after beach erosion, where mother nature takes all the light stuff out, leaving all the heavy items on the beach. And we can dig 200 targets (while editing in all conductors), and NEVER dig a piece of foil or tab. And while the dry sand won't afford that type of sluice-box effect (nor wet sand that's not "going out"), yet still, swimming (even if only wading and frolicking at the water's edge) is MUCH more conducive to jewelry losses.
And this need not necessarily be ocean beaches. Even fresh water beaches inland are the same psychology. And if no beaches/water near you, you can hone your land hunting to places where junk is less and jewelry odds are better: Sports venues (athletic fields). As opposed to picnic/eating zones, which are a natural recipe for aluminum junk.