My Review of the 8-inch Concentric Coil:
First of all thank you Deeptech for listening to your customers and producing an excellent coil! Before I begin discussing the concentric coil I want to discuss my experience with the DD coils. In general, I like the Vista-X it goes deeper in my soil than the Blisstool and has better separation, but there have been a few issues for the types of sites that I hunt. The main issue is the sensitivity of the X to bottle caps and bits of rusty cans, which are everywhere where I hunt. I have learned a few tricks to identify flat iron, such as listening for an iron tone at the end of the signal and what I call an “edge check”. An edge check is where I swing slowly across the target using short swings while slowly backing away from the signal to just catch the edge. For flat iron, the high tone goes to an iron tone as you approach the edge, while for a good signal, the high tone fades away to nothing. This works, but for a site littered with flat iron it just slows me down too much and I am forced to switch to my Equinox. The 8” concentric changed all of that! Just like on the Tesoros, using a concentric, bottle caps and flat iron can be discriminated out at lower disc level than for DD coils. By setting the X disc at 31 most of the flat iron either breaks up or goes to iron tone and I can still hit nickels and all but the smallest of gold rings. I tested the coil at a very trashy site which has been hunted for at least 10 years. I still hit on some flat iron, but the iron tone at the end was more often heard with the concentric compared to the DD coils and most of the can bits gave iron tones. I still had to do some edge tests, but far fewer than with the DD coils. In the end, the amount of iron in my pouch was no different than for the Equinox, mostly iron with a hole in the middle. This coil will open up a lot of sites for me and I think I will rarely take it off.
Thank you for the review, BigSkyGuy !