The 6" Double-D on an Equinox 800 is the coil I like the best and would keep on an 800 if I had one again, and that's because I work very trashy sites were smaller coils rule.
As for finding more targets in an area you've already worked and pulled about 30 coins from, it does show that the detector and coil work however it does not mean that they work better than other detectors and coils. The only thing that tells you for sure is that you put that coil over a target, and got a good hit, which means you did not put a coil over that target before and got a good hit. The only way to know if one detector and coil are outperforming other detectors and coils is to have all of them together at the same time, and check a located target before any ground disturbance using each of the detector and coil combinations, at the same time, for the same target.
The other method is to dedicate a specific area, in other words to physically Grid-It Off from the surrounding ground, then hunt it thoroughly in the Disc. mode and then using a threshold-based All Metal mode to remove all metal targets.
I just bought a house the end of May that was built in 1933. It has a dirt and rock driveway and a mostly dirt area in the over-size double carport. I've been hunting it with every detector I have at different times since the 1st of June. Every time, I find coins. That's because I am just randomly searching the driveway, even over the same general areas I've passed before, but I have not dedicated my time and effort to clearing out 1 gridded spot. I plan to do that in the future but right now I'm just doing some random searching. No results have proven that any detector or any coil was superior to any other detector or other coil, they only support the fact that targets are present and that I'd happened to put the coil over a good target and made a recovery. You have a very good coil on your EQ 800 now, especially if you're hunting in tough conditions such as a lot of targets, dense brush, building rubble, etc. Maybe when you have the time you can take two or three detectors and, at the same time, search a dedicated area as you mentioned. Mark the spot of a located target before disturbing the ground and check all the detectors and coils at the same time on those located targets. That can help build confidence in your detector and coil selections.
Monte
