They might turn it up pretty high at the factory but never as high as it can go because many can turn it up even higher than factory settings and do successfully.
Mine is turned up further, almost to max, just up to the point of noise then backed down to be stable and quiet.
I can't get closer than 1 foot to a piece of tot lot equipment now before it goes off but I can still find targets next to or even leaning on large iron like that or fence poles by listening for the telltale double beep so max sensitivity does not affect that prime little superpower this thing possesses.
Even hyped up like this I still never have EMI chatter problems...never.
Sounds like yours is plenty sensitive if you can reach 7", if you can get even a bit further with disc in all metal I would probably leave it alone for now.
Those pots are very brittle, fragile and sensitive, one wrong move or an adjustment too far and you can mess things up bad but if you are careful it can be done easily.
I usually hunt with the disc very low or in all metal because you will get the deepest, clearest signals that way, using disc you do lose a bit of depth the higher you go along the range of that disc.
It might not be a whole lot at all, maybe way less then an inch, and all units seem to be slightly different in this regard plus soil types might affect this too but I would rather get signals on everything including the very deep stuff at the very end of the scanning field and figure them out and make digging decisions by thumbing that knob which I do on every target....always have.
Setting the disc and just digging everything that beeps above it drives me crazy even though many do it this way, for me the game of figuring out good from bad and treasure from trash before I dig is much more fun and satisfying.
Over the years I believe I got pretty good at this, maybe not Tabdog good but good enough to cut out digging about 80-85% of the trash I come across and make pretty good educated guesses about the rest.
It sounds like you thumb the knob and do this like I do, this is the only way I do it because over the years I found it is way more accurate than doing it the way all the manuals say to do this.
I always turn past the fade out point then back down and notice where the targets comes in plus I listen close to exactly how the target comes in.
After digging thousands upon thousands of targets I experienced most, but not all, targets that are good will usually come in clear, solid with very little chatter, noise or clicks before they firm up, they just appear, while lots of trash will come in way noisier.
There are exceptions...some trash will come in solid like coins usually do, nickels are weird and out of all the coins might not be so silent until they firm up and really deep stuff can also act differently than shallow targets and not come in so solid, either.
Also that high disc depth loss thing, a very deep high conductive coin like a dime at the very limit of the scanning field may well disc out way before top end where it ordinarily would never disc out at all so you have to be on your toes all the time when making digging decisions.
I also had some experience using an 8" coil model for a couple of weeks and noticed the disc was not exactly as sharp and exact as the smaller coil models.
Very close but not exact...not a deal breaker by any means but just something to be aware of.
This is something you might not notice at all unless you had hundreds of hours swinging the smaller, solid coil units like I have and I do believe this slight difference might have to do with that donut coil but nothing to worry about or concern yourself with.
The little extra depth you might get using the bigger coil pretty much makes this forgivable and a wash for overall hunting in my opinion.
The good thing is all the gold at any size from tiny to large I have found with my Tesoros at 6" or less have always come in solid, clear and a for sure dig-me signal every time from all angles so far, as always super deep gold targets may act different.
You never ever know what you have in the ground below that coil before you dig it 100% but I have found the accuracy of this method is the best way for me to enjoy this hobby by far.
I cannot dig every signal I come across anymore, don't really want to either and without doing that there is always the possibility of missing something but I really don't care and the "what ifs" never bother me because my success rate is way better than I probably deserve or have any right to expect...surprisingly high as a matter of fact so I learned to live with all that.
Plus I hunt my spots more than once anyway so I figure what I don't find one day I have a shot to find on another.
A couple of other things...
It is possible to estimate target depth pretty good with practice, there is some modulation in that signal on normal rings and coin targets and deeper targets do sound a bit further away and shallow targets closer and louder plus by swinging over the top of these target types before you dig if you know your scanning range and do the math regarding the amount of space between the target and the fade out point you can get pretty accurate at this.
Finally there us one more thing that I hope you get to experience one day...the very rare and unique sound of big gold like a class ring and maybe smaller but very high karat gold.
This sound will be different than any other sound you are likely to hear come out of this thing.
Out of the huge amount of targets I have dug with my Tesoros I have only heard it twice, the first time with my Compadre and months later the second time with my Vaquero.
It is my holy grail tone, the one I long to hear every time I hunt with either detector and if I am lucky I will get to hear it again one day.
This sound is slightly longer than normal, clear and sustaining as the most perfectly cast bell you have ever heard and as I mentioned unique.
The first time I heard it was using my Compadre and got a signal that came in exactly at 3:00 on the disc knob.
It was different but I didn't know it at the time and when I dug a class ring instead of a zincoln I was shocked but for some reason that sound stuck with me after that.
Months later using the Vaq I heard it again.
This time it rocked me back on my heels and I remember taking a short, quick breath when it happened.
This signal was the only time in my entire career that I knew for sure 100% what I was swinging over, the only time before I dug it and I was positive it was going to be big gold.
I would have bet you my car with confidence that is how sure I was about this sound....and I was right.
Turned out to be a the exact same class ring from the exact same high school as the first one but just a different year.
Learn this fine tool well, not even close to an actual beep and dig machine like many believe and so much fun to use and learn not to mention highly productive.
Welcome to the world of Tesoro...there are many reasons why we think so highly of these things and why there is an actual cult built up around the Compadre.
We got a church...welcome to the congregation!
