Jim...true most of my parks are devoid of signals at less than 8",,,but the signals that are left are usually left for one of 3 reasons...OR all 3
1) the coin is very deep or on edge...2) the coin is mixed in with crap...3) the coin is in iron...or again all 3
I do have some sites that have very trashy...and at all different soil levels. I usually take my small coils to these few sites when field testing. I have also hit some of them with both the pro coil and the 10 x 12 SEF coil.
My opinion is the same...I always do better with the 10 x 12 SEF than with the pro coil. For me it separates just as good and probably better than the pro coil...but the key for me is not separation believe it or not...because both coils separate incredibly. The key is the end result sound that my ears hear once the machine/coil processes it and sends it through the Sunray headphonhes.
I personally get a lot more "diggable" signals with the SEF coil and that's as honest as I can be.

1) the coin is very deep or on edge...2) the coin is mixed in with crap...3) the coin is in iron...or again all 3

I do have some sites that have very trashy...and at all different soil levels. I usually take my small coils to these few sites when field testing. I have also hit some of them with both the pro coil and the 10 x 12 SEF coil.
My opinion is the same...I always do better with the 10 x 12 SEF than with the pro coil. For me it separates just as good and probably better than the pro coil...but the key for me is not separation believe it or not...because both coils separate incredibly. The key is the end result sound that my ears hear once the machine/coil processes it and sends it through the Sunray headphonhes.
I personally get a lot more "diggable" signals with the SEF coil and that's as honest as I can be.