SEF 15x12 First Hunt! She's A KEEPER!

[Critterhunter]

I've reached a few conclusions about the 15x12 and am ready to pass judgement on it's depth in my medium to high mineralized ground. Over the last few hunts I put the stock 10" Tornado on and took it to a known deep coin spot I've recently used the 15x12 at. The 15x12 has failed to even produce wheats at this site which seem fairly plentiful at this location in the 7 to 8" range and deeper.

As is the norm for me I calibrated sensitivity on the 10" coil just like I've done there with the 15x12- By sticking a silver dime in the ground at fringe depth and calibrating the sensitivity doing the Sovereign wiggle until the easiest 180VDI with good audio is produced. My normal routine is to keep sticking the dime deeper until a very narrow window on the sensitivity dial is found. It may ID at other settings but once it's deep enough it becomes rather obvious just what setting on the dial produces the best ID with the least amount of work.

I'm rather picky about this and will keep moving the sensitivity up and down the dial to confirm the best setting at least three or four times. I'll go much too high and much too low, then narrow the best response down to "half hour" changes until that precise spot is found. How easy a 180 reading with good audio is able to be achieved and also how well it holds is my criteria when things starts to narrow down to a specific spot. It's not uncommon for me to waste a good 10 to 15 minutes playing with the dial until I've confirmed several times that one spot seems optimum. Often I'll find that once I've got a spot in mind anything even slightly higher will create a much more unstable VDI that is not as easy to hold at 180, and anything lower will make it more work to cause the VDI to climb and lock onto the proper ID.

That's a good way to tell if your sensitivity is too high or low. If it's too high the VDI will be more prone to randomly jumping around and not climbing the VDI at a somewhat steady progression. Too low of a sensitivity setting will often cause the VDI to sluggishly climb- 140's, 150's, 160's, 170's...and more often than not it will fall like a stack of cards before reaching 180 and you must try to make it climb the dial all over again with the wiggle.

Often you'll find that too high a setting will actually null out the target here and there the same way too low can. Other times the best setting isn't as obvious. When that happens either pay close attention to just what setting produces the VDI & good audio with the least amount of work and is easier to hold, or I recommend sticking the dime another inch or two deeper which will make that setting more distinct. When it's at fringe depth (for a freshly buried target...expect more depth on something undug) the sensitivity setting gets very tight and easier to see at most locations. At others a fairly wide range might seem to give a decent ID but sticking it deeper will quickly narrow things down. Otherwise pay attention like I said to just how much work is required with the wiggle to get proper ID. More randomly unstable means too high, sluggish climbing (which can be somewhat random but you'll see that it's constantly continuing to climb) and almost never quite getting to 180 means too low.

So anyway, having recently hunted this site with the 15x12 with similar moisture content (very dry) I found that the calibration on the dial was around 2PM. With my two hunts over the last few days with the 10" Tornado that "best" setting ended up being about 11PM on the dial, quite a bit higher than what I found for the 15x12. Being that wheats seem to be all over this place (for wheats) and start at around 7" deep and go deeper from there, this is a good indication of just how deep a machine or coil is getting. If you aren't popping wheats you can bet your depth is topping out at probably around 8" or so max depth, at least on those coins.

The 15x12 didn't produce any wheats at this location after 3 or 4 hours of hunting on at least two separate days. The 10" coil in that same amount of time produced two wheats on one day and one or two wheats on the other, all ranging from about 7" to maybe about 8 & 1/4" deep with perfect ID and tone. Had they been another 2" deep I'm fairly confident I would have got them with no problem. Fairly impressive for a medium mineralized location and these super dry conditions. This soil also tends to be a black powdery texture almost like talcum powder- which equals less conductive conditions (at least in it's dry state) than your typical good black top soil.

So I have come to a few conclusions which have built up over time but came to a head with these recent hunts. Interestingly enough there is the BIG difference and VERY important in distinctions here, so really think about this...At this same location if I were to set the sensitivity to the highest possible while retaining a stable machine (as most hunters do....although I disagree this provides most depth on a Sovereign, unlike other machines) the 15x12 will always allow a higher sensitivity setting than the 10" coil riding that edge of stability. In fact, I can't remember a single location when I tried this (as I was prone to calibrate sensitivity before until finding out better) where the SEF coil didn't allow for a higher sensitivity setting than the 10" coil before becoming unstable or noisy/nulling. All the times I can remember when riding that edge the SEF allowed quite a bit higher sensitivity settings without the machine getting too noisy for me to handle. More often than not this coil is smoother at higher settings than the 10" is at a somewhat lower setting.

However, as I've hammered away at endless times before- I've found at least in my soil that max sensitivity doesn't equal more depth. Here's that distinct difference I was talking about and a clue as to why the 15x12 isn't deeper *in my soil*...While it allows higher sensitivity than the 10" coil in terms of the machine still running stable, my buried dime calibration test has both coils switching the lead in terms of which one ends up at a higher setting on the dial. When doing the buried dime test at this location on several occasions with both coils with the exact same moisture conditions (as dry as it gets), the 10" coil has ended up at about 11PM on the dial when as the 15x12 has ended up at around 2PM.

Think about that for a moment. There in lies the difference. The 15x12 is built in such a way that it runs smoother and at higher sensitivity settings, yet the 10" coil with the buried dime test ends up with a much higher sensitivity setting- much closer to "max unstable sensitivity" for either coil (but still not at instability and so very smooth). The results are more depth for the 10" coil, at least in my more mineralized locations. On the other hand, at a few sites where the soil conditions seemed better the 15x12 got me deeper than the 10" would have. For instance, at the beach the 15x12 seems a good 2" deeper on the same coin to me.

In summary- Do most say the 15x12 is deeper than the 10" or 11" Pro Coil and a bit deeper than 12x10? Yes, they do. Do I think this coil is deeper at most of my sites than the stock 10" coil? No, I don't. I have no doubt this coil is deeper for most people but I would bet that that's only the case when the ground minerals are something less than medium in content. Although the machine will run smooth at very high sensitivity settings using this coil, I believe the target is being lost in the larger ground matrix that this coil is taking in. That doesn't mean it isn't more stable at higher settings, but it does mean the machine can no longer process and separate the target signal from the ground matrix as easily. That is where the difference in depth is I believe.

However, at some of my sites with seemingly less minerals the 15x12 has got me some tiny targets at impressive depths (like 11" on something about the size of your pinkie fingernail, or say a half dime). What I've concluded is that if you are hunting a location where the ground minerals aren't real high then the 15x12 will probably offer you more depth, but if the ground has some fair mineralization then it will not get as deep as the 10" coil on coin sized targets. It's deep just the same. Even running in Auto about 8" on a coin isn't nothing to sneeze at as most machines on the market max out at around 7.5" in my soil on a silver dime. It's coverage is awesome. Great for things like open fields and the beach. It's weight isn't a big issue to me, but I'm using spray on liner on it and no coil cover to save 3.6oz of weight. It's pinpointing is better than the 10" using the tip or tail of the coil and the base of the "V". It's separation width (left right wise) is like that of a 8 or 9" coil on other machines, even better than the stock 10" coil. It's stability even in heavy iron or minerals is something to behold. It seems to like coins on edge or even masked in certain ways better than convention double D or concentric coil designs. On a scale of 1 to 10 I've give it a 9 in all respects, and it would have been a 10 if it had showed me consistently deeper target ability than the 10" in my soil.

I would highly recommend this coil if you have lower mineral sites where I'm sure it's depth will shine greater than the stock 10". I would also recommend it for large open areas or beach hunting. As said, it appears to get deeper on the beach than the stock coil for me for some reason. If, however, you feel your ground is medium to heavy in mineral content then I would look into either the 12x10 or S-12. I feel those slightly larger coils may still provide more depth because they might not be soaking in too much ground content. Currently I'm looking to trade my 15x12 for the 12x10 or possibly the S-12. Only because more depth is my primary objective with coverage being an important but secondary factor. If I was strictly a beach or large open field hunter the slightly less depth of the 15x12 over the 10" coil wouldn't be an issue, but more often than not I'm hunting pounded spots where even an extra inch of depth can mean the difference between success and getting skunked that day.

Is it a better coil in all respects than the 10" coil? Yes, IMHO. Is it deeper in medium to heavy minerals? No, but it is on my beaches and I would bet money that it will be in lower minarlized locations. It has been to some extent for me at certain spots. It's just as luck would have it those spots aren't known deep coin locations where I could really see this coil excel. Is it a great water coil? No, too much drag IMO, but I tend to swing more towards a medium sweep speed than the ultra slow that most Sovereign owners prefer. I would have no problem recommending this coil for anybody who wants more coverage, or anybody who land hunts in lower minerals or beach hunts a lot as I think it will show you greater depths in those circumstances. It's sensitivity to even tiny little earring backings is impressive. I've dug shoe lace holes 7.5" deep with this thing even in my more mineralized land sites. It's a great coil, but if your main goal is maximum depth and your ground is medium to high in mineral content then as I said I would look more closely at the 12x10 or S-12.

I'm torn between those two coils for one reason only. With the fantastic separation of the 15x12 I can only imagine how much better the 12x10 is. On the other hand, the S-12 is a legend and I love the S-5 coil they also make. That little coil gets 7 or 8" deep even in Auto sensitivity so I can only imagine what the S-12 can do. Which of these two coils is deeper is up for grabs. I've seen no comparisons of the two in head to head field tests. I would suspect the 12x10 is deeper or at least will match it in depth, and I know for sure the 12x10 will separate better just based on the unique hybrid coil dynamics of these SEF coils versus a convention DD such as the 10" and thus the S-12. I'm fairly confident that either one will max out coin depth in my soil conditions, not surpassing the point of no return in terms of coil size versus ground matrix. Something slightly bigger than the 10" coil's already impressive depth might give me even a little more depth in my soil, but anything bigger (15x12 or WOT) I feel will not increase your depth on coin sized targets if your soil is medium to high in mineralization.

If anybody has compared the 12x10 and S-12 in depth please post a report. As said, I'm in the market for either one but would prefer the 12x10 at the moment. If anybody wants to trade one for the 15x12 shoot me a PM.

 

[Critterhunter]

Forgot the most important fact/theory- Since the 15x12 more often than not appears to allow higher sensitivity settings before becoming unstable if you are one to ride the edge of machine stability, one might conclude that in lower minerals max sensitivity equals better depth. If you are in that camp (max sensitivity equates max depth) then in that respect it might be that the 15x12 will get much deeper than the 10" coil. In my soil, though, max stable sensitivity doesn't equal maximum depth. Something much lower provides best target ID audio as I've found with my buried dime calibration tests. I hope you get the point I'm trying to make above, though...This coil will run at higher sensitivity settings. If you believe at least in your soil that that is going to mean best depth then that is the most important distinction of this whole message. If you often find that something like my calibration test gives you max depth usable sensitivity which is much lower than max stable, than I would suspect that this coil will not go deeper for you as your mineral content is beyond that point where this large of coil produces deeper results.

The only weird thing about this is that my sand beaches tend to be highly mineralized. All machines prior the the Sovereign (including my Explorers) got less depth in the sand than they did on land. The Sovereign is the first to go even deeper. 12 to 14" deep on a coin isn't a problem for either one of these coils on my beaches, though I suspect from the feel of it that the 15x12 gets another few inches deeper in the sand than the 10". That's the thing I can't figure out. One would suspect the same results on land then. It's just weird in the first place that this machine's already impressive depth on land is even more outstanding on the beach.

 

[Critterhunter]

In yet I hope is a more clear summary- Ask yourself this...Do you find max stable sensitivity is providing you best depth in your soil? Or, do you find that my buried dime test provides you with max depth and that this setting is much lower? If the edge of stability provides you with max depth in your soil then I would bet the 15x12 will get deeper, as it often will allow higher stable sensitivity settings than the stock 10" Tornado. However, if you find that a buried dime calibration ends up with sensitivity much lower than max stable then I would suspect that the 10" coil will get deeper. Chances are then that you have medium to heavy mineral content and as a result can not benefit from the higher stable sensitivity settings the 15x12 provides. Even if it's max stable setting is much higher than the 10" coil I think the much larger ground matrix this coil is taking in is causing the Sovereign to lose the target in that matrix. However, the only exception I've noted is that my beaches are mineralized yet the SEF seems to provide a few more inches of depth over the 10" coil in those cases...And this is still doing the buried dime test to calibrate sensitivity. As I have found *in my soil*, riding sensitivity to it's edge of stability gives me less depth with either coil, probably due to my higher mineral content. The difference is there- The 15x12 will allow higher settings while being stable, but when calibrating with a buried dime the 10" coil ends up being higher in sensitivity and thus seems to get more depth than the 15x12. Both of these coils calibrated this way are still well below max stable sensitivity, but I would say the 10" ends up being much closer to max stable sensitivity than the 15x12. I believe this is where the "headlights in the fog" theory really becomes clear. The 15x12 may be able to turn up it's beam higher while remaining stable, but the increased ground matrix this larger coil is seeing erases any depth advantage it may have...at least in medium to high minerals. The smaller 10" coil's field of "vision" allows it to pick out and see a deep coil more easily than the 15x12, regardless of how or why either coil is calibrated in sensitivity.

The usable sensitivity range of the 10" coil, while lower than the 15x12, is higher when it comes to where the buried dime test puts sensitivity on the dial. I realize I've hammered away at this concept several times in the past few messages but I'm wanting to make sure people understand the differences here in theory. Something like the 12x10 or S-12 in my soil might provide slightly more depth than the stock 10" coil because they aren't overwhelming the machine's processing ability in terms of separating the target signal from the ground matrix.

This isn't unique to the Sovereign. In fact, this headlights in the fog theory is more pronounced on other machines on the market. I've had sites where the Whites 5.3" coil provided more depth and better target IDs than the stock 9.5" coil. This was due to the 9.5" seeing too much in the way of mineral content, ground matrix, or tiny hot rocks (black sand). Every machine has a point of no return in terms of coil size versus the heavy mineral content they are taking in. I believe in my soil the 15x12 is past that point. In every respect this coil is better than the 10" stock coil, but in terms of depth in my soil I don't believe it's as deep. Sure, even in Auto it's still impressive and deeper than most machines on the market, but the 10" coil gets even deeper for me. If I wasn't short on cash at this moment I would keep the 15x12 for my beach and wide open area hunting and buy the 12x10 and S-12 to see if they get deeper in my soil than the 10" stock coil. As it stands I'll have to trade this coil off in order to obtain one of the other two for field tests.

 

[Critterhunter]

One other thing on this subject that comes to mind...When talking about ground minerals or tiny hot rock content don't forget about one other important factor that may limit the depth of larger coils. When people say iron more often than not they are referring to old nails or other bits of junk left behind by humans. Another form of "iron" is the iron that soils can contain more or less on a natural bases. Often people don't think of iron in this respect and when they hear talk of mineralization they assume it's something other than iron. While that's true largely there are areas where iron is the primary deposit in the soil more so than anything else you'd call "minerals", yet it doesn't exist in any form that can be picked up and looked at. This is when the iron is in high quantities in the ground matrix just like anything else you'd refer to as mineralization.

So what happens when your coil is going over a target and also taking in a large picture of iron "dust" in the soil? I believe that as the picture taken of the surrounding soil gets bigger with a bigger coil, there comes a point when the amount of iron seen along with the target can degrade target quality or perhaps even null it out. The target gets lost in the ground matrix and the machine can no longer separate the two. That's also where too large of a coil can actually get less depth than a smaller one. You can replace "iron" above with any other metal or form of mineral that may appear in high quantities in the soil and see the same theory behind it. Bigger isn't always better, otherwise we'd all be hunting with coils 5 foot in diameter. There has to come a point when size increase no longer means increased depth, and just the reverse begins to happen as the target gets lost or at least largely degraded by the extra amount of ground content the coil is also seeing.

I'll hijack the old "headlights in the fog" theory that has been kicked around in metal detecting circles for many years. For the few who haven't heard this analogy it goes like this- Say you are driving down the road in a heavy fog and turn on your high beams. You instantly notice that you can not see quite as far ahead with the high beams on than you could with the normal lights. The same situation can be seen sometimes when driving in a heavy snow. The glare of the light off the snow flakes makes you less able to see past that and into the distance. This is the comparison many have used in the past to illustrate that more (higher sensitivity) can often mean less (equals less depth). Some look at this two different ways. One, the signal is reflecting off the ground matrix more and doesn't penetrate the soil as well. However, that's not really true in terms of how most machines handle sensitivity. Rather than turning up the strength of the field signal being sent into the ground, many machines adjust sensitivity by increasing or decreasing the received signal gain coming from the coil. But the theory still applies- The higher the RX signal is amplified the more the "glare" or "noise" also gets amplified, and there comes a point when the target signal gets too far amplified and distorted (with introduced noise or headlight glare) for the machine to still process and separate the target signal from the matrix it's awash in.

My additional comparison to this analogy would be this- Have you ever used a flashlight that features adjustable focus of the beam of light? Let's say you go into a dark room and are trying to see something at the far distant corner of the room. With the flashlight unfocused (wide beam) the item you are looking for isn't easily seen. Not only is it not lit up as bright as it could be, but your eyes are being distracted by all the other things off to the sides that are closer to you and so being more lit up by the wide beam. Now imagine that you take that light and narrow it's beam down to something more focused. In that case you can now probably see the distant item because your light is directly focused onto it without also lighting up (detecting) the other non-wanted items off to the sides.

The same thing can be said for coil size versus depth, and I'm not talking about because of it picking up nearby trash targets and thus masking the desired one. Simple mineral or iron content around the target in the soil can be "lit up" by the coil and cause the machine to be unable to focus on the specific target it's after. The size of the coil is now too large to equal returns in depth. Something smaller can "see" deeper because it's no longer overwhelming the machine with so much more information in the form of ground matrix that it also has to sort through and ignore to pick out what it wants. In heavy trash that scenario is obvious because nearby trash may also get taken in and so masks the target, but many don't consider that ground minerals, metals, or even iron in microscopic form that is saturating the soil can also act in much the same way.

Where the compromise for max coil size while still increasing target depth lies is a highly subjective and variable area. It depends on your ground conditions in your area, and can even vary from one site to another in your location. I've seen 6" coils get better depth than a 9 or 10" coil or larger in some bad spots based strictly on the ground matrix and not because of masking by trash. By the same extent on the Sovereign it appears my 10" coil is doing the job of a 6" coil on other machines, owing credit to the excellent ground handling capabilities of BBS machines. Perhaps I can push that depth a little deeper by going to the 12x10 or S-12 without going past that point of no return that the 15x12 seems to have gone for me in my soil. At some spots (beach or less mineralized ground) the 15x12 shows greater depth due to it's outstanding stability at higher sensitivity settings than the 10" stock coil, but I do believe at most of my sites it's hurting my max depth ability rather than hurting it, all due to what I've discussed above.

 

[Mentez]

A couple of things worth a mention.

I'm getting the 10x12 SEF in a few days.

I did a little test today while out on a fairly mineralised site. I had just found a victorian half penny - 1864, so used it as a test coin. I dug it down to 8 inches, laid it flat and played with the settings. At disc ON, sens auto the signal came through loud and clear. I took this as no test of capabilities at all, so re-dug the coin and extended the hole to about 12/13 inches and laid the coin slightly on one side so the edge was mostly pointing upwards.

Set the GT to sens auto, and disc on.....nothing. turned the sens to 2pm...nothing. It just managed a slight blip at 12, but the funny thing was if I increased the sens any more the machine gave a totally mixed bag of signals on the target. In fact it would have put me off digging. I totally subscribe to the "headlights in fog" analogy to sensitivity. I hope the SEF 10x12 will help this even more.

Oh, and by the way, about 30 seconds into todays search I found a beautifully preserved roman bow broach!! Best one I've ever found. Spent the next hour chasing shadows....but that's the fun of detecting!

 

[synthnut]

Mentez,
One of the great features of the SEF coil is to read coins on edge !!...I'm going to order the 12 x 15 SEF as I would like a coil for more coverage for my beach machine , but I am REALLY interested in hearing from you on the 10 x 12 SEF .... Thanks, Jim

 

[Tony in FL]

Critterhunter - do you do the dime calibration test mentioned above on every hunt, just when you go to an unfamiliar location, or just when you are researching differences between coils?

 

[Critterhunter]

Mentez, I'm glad you seem to have found the same thing I have- That too high of sensitivity can null or degrade a target just like too low can. Thanks for the report.

Tony, I stick a silver dime in the ground at the start of every hunt. Even if I've hunted a site the day before I'll still re-calibrate the sensitivity doing the dime test. Reason why is moisture content can change, and even if it hasn't rained the moisture content of the air I believe has some impact on things. Regardless of all that, on any given day something like stray RF noise might effect things one day and not the other...So I believe it's a good idea to re-calibrate sensitivity even at the same site on two different days. Just part of my normal routine now. First thing I do is set sensitivity at about 2PM and look for a clean spot. If 2PM is falsing I'll either go lower or throw it into Auto to find a clean area. The way to tell if a null is iron or just from too high of sensitivity is if it keeps repeating in the same spot. If it doesn't then it isn't iron, but if it does over and over I'll move to another spot to dig my hole for the dime.

I just got back from a 5 hour hunt on the beach sand (no water hunting today) at one of the beaches on the great lakes. I gridded the entire beach from the very edge of the water all the way to the wood line at the back of the beach. I probably covered at least a football field or perhaps 1 and 1/2 that size. I was using the stock 10" Tornado coil and found something out that might be of interest to potential 15x12 users...

Prior to today I've only hunted this particular beach with the 15x12. By doing the buried dime test I think I ended up at around 2PM there and the 15x12 was smooth as butter as well as giving me about 8 to 10" of depth on coins, perhaps an inch or two more than that. Regardless, although I set sensitivity via the dime test I could have raised the sensitivity even higher to maybe as high as 11PM or so and the threshold would still be stable. As I've also said before the 10" coil has got me coins at about 11" deep (with more to give based on the solid response) where as the 15x12 has only thus far got me coins about 8 to 9" deep on land. They seem to reverse leads on the beach though, with both coils getting really deep (like around 12" or more) on coins but with the 15x12 getting another few inches more depth I think. That's sort of odd in that one does better than the other on land, they both do even better in sand, but the 15x12 takes the lead on sand where as the 10" Tornado thus far has been deeper for me on land. Not sure why that is. Perhaps the mineral content of my soil is just bad enough to keep the 15x12 from showing more depth yet in the sand it's just low enough (but still fairly mineralized) that the 15x12 is able to take the lead by virtue of it's size.

Anyway, so today I hit this beach with the stock 10" coil and started sweeping around for a clean spot to bury the dime. At 2PM the threshold was unstable (random nulling) so I lowered it to about 3:30 or 4PM and the threshold was still bombing in and out. Flipped over to Auto and the machine finally stabilized. Stuck my dime in the ground at about 6 or 7" deep and was able to hit it fine in Auto. Flipping over to manual anything but almost full lowest on the dial was nulling out my threshold, and once I found a stable (almost all the way down) spot for it it wasn't picking up the dime very well at all. After more testing I found that there was no happy compromise in manual. High enough (2 to 3PM) to pick up the dime and my threshold was driving me crazy going in and not due to the ground minerals. Low enough to get the threshold somewhat stable was not hitting as well on the dime as Auto was, so that told me Auto was my best option for today's hunt.

What's weird is this...The 15x12 has run nice and stable at this site at like I said around 2PM or so. The 10" Tornado was highly unstable and pretty much not usable unless I ran in Auto and then it was smooth but still with the occasional false like every 6 or 7 sweeps where as the SEF coil never even really gave me any trouble in that respect. I'd say from memory at this spot the SEF at 2PM was maybe giving me about 8 to 10" on a coin, maybe another inch or two deeper. The Tornado could just barely manage about 7 to maybe 8" on a coin today. I found the fact that these coils seem to switch leads for me on land versus beach rather curious before but today's hunt made things even more prominent in my mind as to the difference in performance of the two on my fresh water beaches. That one for sure has me scratching my head and as said I can only figure my soil has too high of minerals or just the right mixture where the 15x12 is just too big (though smooth even at higher sensitivity settings than the 10") to not show an increase in depth. In the sand, though mineralized, perhaps it just not quite as high or just the right mixture again to where the 15x12 shows it's size advantage in depth over the 10" coil.

I was really kind of tweaked about the poor performance the stock coil had today. I would have expected that kind of low level performance from any other machine on the market but at the beach is where the Sovereign really shines and shows even more than it's already outstanding depth on land. I'd have to say it's depth today was the worst I've ever seen of this machine on land or on the beach. 6 or 7, maybe 8, inches in depth is pretty lack luster for a Sovereign. At other beaches either coil has gone much deeper and with more solid of locks. Some of the coins I dug today would only give a proper response from one direction and a bad one or a null from the other.

My total finds for the day were about $6 in clad (5 nickles, $3 in quarters, etc), about 8 of those big hoop junk earrings all bundled together as one (who thinks that looks good to wear?), another junk earring about that size but solid and made from aluminum (didn't think you could get more ugly than hoop earrings but I was wrong), about 15 square tabs, a couple round tabs, three pop cans, the usual assortment of junk, and the highlight of the day was a large ring about five feet from a garbage can. At first glance I thought it was white gold and that would have been a good hunk of change in scrap, but on closer inspection I could see it was junk metal. Heading back there by the weekend to finish off this beach and then I'll be off to the next one to clean out as fall approaches.

Scooped any signal that broke through any kind of null. Didn't care how bad the response was and it's a good thing because many of these coins were bottle cap quality in poor responses even at 6 or 7" deep. I kept thinking "this has to be a bottle cap or some piece of junk" only to pop a quarter or some other coin and thought "Wow, I never would have expected that poor of a response from my GT at those shallow depths." So it appears that if anything the 15x12 is respectable in my soil on land beating most machines on the market if not the 10" coil, but in the sand this coil seems to put the pedal to the metal and pass the 10" coil. If I had the money it would be worth keeping the 15x12 just for my sand hunting but at this time I've got to trade it off if I want to try the 12x10 or S-12 to see if they get me more depth on land than the stock 10" coil. My primary goal is max depth on coins in my old parks and such. Coverage is important (and the 15x12 is awesome at that) but secondary to me. It's not like the 15x12 isn't deep on land. As I said even in Auto it's still beating most machines on the market at around 8 or 9" on coins. In the sand it's unreal how deep it goes, and I'm also constantly amazed at how deep and hard it hits on tiny little bits of metal. Seems it should have no problem hitting coins as deep and deeper than the 10" coil on land but I just haven't seen it.

Still wondering if any Sovereign owners have compared the S-12 and the 12x10 in depth on coins. Which was deeper and what kind of soil were you hunting? I would expect the 12x10 to at least match the S-12 in depth and I'm almost positive the 12x10 is going to separate better since my 15x12 seems better than even the stock 10" coil at left/right separation. Another thing I wonder about is the 12x10 might surpass the S-12 in depth in high minerals primarily because the detection field seems squeezed width wise on these SEF coils. It still runs from tip to toe just as deep as a regular double D but it's awesome pinpointing and separation is I feel because the width of that field is compressed. For that reason maybe this coil sees a little less ground width wise than the S-12, which could mean less ground matrix in the picture and thus more depth on coins without getting lost to the minerals....If you can follow my logic in theory here. Sure would like to hear from somebody who has compared them both on coins at depth and what kind of soil you were in.

 

[Critterhunter]

Got a PM that might pertain to the coil size/depth in high minerals debate. Name withheld....

"I have an 8" Tornado, 10" Tornado, (2) S-12's and a 15" WOT. Your post about trading your 12" x 15" SEF got me curious and I was just checking to see if you had completed the trade. Not that I need another coil sitting around. Actually in my soil, the 10" Tornado hits the hardest (not sure about the beach)."

I find this interesting if I'm reading it right. Even the S-12 and WOT isn't hitting as hard on land as the stock 10" coil. I would expect some degree of mineral content then. I'm really hoping the 12x10 I have coming in trade this week will give me more depth without stepping over that line (seeing too much ground matrix and so getting less depth). I would figure the 12x10 will be seeing less ground signal than the S-12 because of the way the detection field's left/right width seems to be compressed to something thinner (though just as deep or deeper) than convention DD designs. I always felt the left/right field width of the 15x12 was tighter than the stock 10" coil...at least towards the tip and tail of the coil. In the center this coil's concentric hybrid part seems to put out a signal roughly the size of a medium soup can, though it seems no worse at separation in it's center than the stock coil. It just gets better out towards the tip or tail when I'm investigating targets.

I really hate to let the 15x12 go as it's way deeper on sand than the stock coil. I just don't have the money to keep it and still try the 12x10 at the moment. Down the road I'll probably buy another 15x12 if only to use for my sand hunts or when I'm trying to grid vast large areas like open fields. If the 12x10 is only "as deep" as the stock coil I'll still be happy. I know it'll be better in all other respects based on how the 15x12 was. Increased coverage is another plus. The stock 10" coil feels too small to me now having got used to the 15x12. It's so much easier/faster/more thorough to grid out big open areas with that coil. It's extra length/width also seems to sync up with my walking speed. With the stock 10" coil I find myself having to hold my steps back a little more than what's normal for me in order to insure proper coverage. It's not quite big enough to cover the ground properly with each sweep as I try to sync up with my slow walking speed, so I find myself holding a foot in mid air until the 10" coil finishes up it's scan of what's in front of me before I can take the next step. It's kind of surprising how something little like that can really interfer with a lazy day's hunt. I was just gridding another section of a beach I've been working the last few weeks and kept thinking that to myself. Just a bit more coverage will do, so I hope the 12x10 gives me just enough to mesh with my walking/swinging speed better than the stock coil does. For sure I'm going to miss the fantastic coverage of the 15x12. Man, I guess I have to let it go in order to see what the 12x10 will do in my soil.

 

[Critterhunter]

I should have my 12x10 in a few days. So long as the short is in the cable at the connector I shouldn't have any problem fixing it, and the owner has guranteed that if I can't fix it they'll swap me back. $50 plus the 12x10 for my 15x12 is a good deal. Of course you can expect a bunch of field test reports on this coil compared to the 15x12 and the stock 10" Tornado. I'll probably start a new thread just for the 12x10.

I was talking to somebody on the phone yesterday that has/had the S-12, various 8" coils, and the 12x10 and 15x12. This person is primarily a beach hunter and told me that when they tested the S-12 on some smaller pins and such made from brass (I believe) the S-12 would not pick them up. They said the 12x10 seems to have better sensitivity for them on smaller targets than the S-12, and got a thin gold chain with the 12x10 with no clasp or pendent to help it being detected. I know the 15x12 to me seemed more sensitivity to tiny little objects than the stock 10" Tornado. I would suspect the 12x10 to be even a bit more sensitive to small stuff like gold chains. I know in the official field report on it this coil got about a half inch better depth on a tiny cut quarter penny (smaller than a half dime). Both coils were deeper than the stock 10" Explorer coil and many report them both to go deeper than the 11" Pro Coil, as well as hitting masked or on edge coins better. I remember reading a few field reports from people who gridded out spots with the 11" Pro Coil and were shocked that the 12x10 was finding both deeper coins and ones relatively shallow that the Pro Coil just plain out missed due to being on edge or masked or something. The Pro Coil is one awesome coil but the main complaint I've read about it is that you find yourself digging a lot more phantom signals with it than the SEF coils, not to mention it being more noisy.

 

[crazyman]

The 10X12 SEF is the only large coil that I'm tempted to try. The 10 inch stock coil is OK but I usually have to run in auto sens. or low manual sens. with iron mask off to keep a stable audible threshold in my ground. I use the Sunray S-8 about 90% of the time and can run manual sens. at 1:00 most places but generally 2:00 works better with my medium sweep speed. After comparing the two I'm pretty sure that I get better depth with the S-8 at 1:00-2:00 sense. than I do with the 10 inch using auto sens. so I would be happy if the 10X12 added some depth but even if the 10X12 is more stable than the 10 inch and would at the least give me the same depth as the S-8 I would pick one up for the extra coverage alone.

 

[Critterhunter]

Crazyman, I have no doubt your minerals are a bit worse than mine but I find it interesting that we've kind jelled into the same settings in some ways. Here's where you might want to try the 12x10...I feel based on my use of the 15x12 that the coil in a sense sees less ground than the stock 10" Tornado. How can that be since it's 15" long? True, it's seeing more ground in that respect but I feel the width of the detection field is compressed which accounts for it's outstanding separation and pinpointing. In that sense I feel it sees less ground in a good way. Still gets the depth and coverage (since it's a straight line tip to tail like any other DD for the most part), but it's not "bleeding" off into space in terms of it's left/right signal pattern. Probably not doing a good job of explaining what I mean but I hope you get what I'm trying to say. Think about it. Many report these coils run smoother in high minerals, iron, and hot rocks. I know the 15x12 did for me compared to the excellent stock coil. Why is that? Besides it's unique field dynamics and it's internal design making it stable, I feel that maybe it also runs smoother because it's "riding" on less ground signal. If that's true then I expect the 12x10 to see even less ground than perhaps a conventional round 12" coil or even a the stock 10" coil. The 15x12 to me felt like it had the depth of a 15" coil yet with the separation of about an 8 or 9" coil left/right width wise. If it follows suit then I expect the 12x10 to have the depth of a 12" coil yet with the left/right width wise separation of perhaps an 8" or even smaller coil as well. In that respect I'm counting on the 12x10 to perhaps see less ground matrix than even the stock 10" coil and so penetrate the ground minerals better without lighting up too much of that matrix around the target. If the theory pans out then just like an 8" coil is giving you better depth in your high minerals than the 10" coil, the 12x10 might be a happy medium. Just big enough to give more depth, yet seeing less ground in a sense and so not losing the target in the fog type of deal. That's why I think the 15x12 didn't show increased depth in my soil, yet it did in my high mineral sand. I won't go further because I realized I've hammered that point away over the last few days in several threads. (Sighs of relief...)

See the auto/PP thread as I just touched on this Auto/manual thing on a bad beach. Very much running into what seems the norm for you in your area at this particular beach. I can relate where the 8" coil would give you better depth and be able to run in manual where as the 10" coil really rough sites can only keep stable in Auto. Never seen such a hard spot for the Sovereign. I would have expected this kind of trouble for any other machine but not it in a place like this. Just the same, it's ran much smoother and with better IDs at some of my other spots where even my Explorers had fits. In that respect it's still better at most sites for me, just that this one in particular has it's number using the stock coil. You'll probably be interested in hearing how the 12x10 does on that beach for me compared to the stock coil. If it does better and allows manual to be used then I bet it would be the same deal for your area.

 

[Critterhunter]

Got this remark in a PM and I'll leave the name out to keep it private...

"I wanted to buy a 10 by 12 for the sovereign but the guy I hunt with talked me into a 12 by 15. We relic hunt open fields and I needed the coverage. Well the verdict is in and I like it. I have a dime buried at 8 inches and it will nail it every time. Also a bullet at 12 inches. It appears to be one hell of a coil. I may get a 10 by 12 later on."

Yes, it's an outstanding coil. My short summary is this...

It did not seem to get as deep on coin sized targets than the stock 10" Tornado in my medium to high mineral land sites. Well, it might have got as deep but no deeper at least at some sites. I think this might be because it was seeing too much ground and thus washing the target in too much ground matrix, even though it would often run more stabile at higher sensitivity settings than stock.

I also found that often it got better depth with a lower sensitivity than what was max stable. I stick a silver dime in the ground at fringe depth for that site and then adjust sensitivity for best response. You want to get the coin at the fringes of depth to where you can just muster a good response with the right sensitivty setting. Something real high but stable might null or degrade target response, and often around 2PM or so was the best setting where as 10PM might be stable too but gave a worse response. Do short wiggles over it to try to achieve best response. Once set, try normal sweeps over it at different rates of speed. Sometimes it wants a faster hunting speed, sometimes lower. Use that speed while hunting, then do the short ones over it to pull the best ID. Also, the speed of the real short investigation sweeps or wiggles is sometimes faster or slower. Remember both speeds while hunting. In my soil I do this calibration with all my coils. Sometimes they respond best at max sensitivty that is still stabilte, while others they want it lower.

Back to the coil...Pinpoints better than stock using tip or tail of the coil even just pinpointing in discriminate. Also, use the tip or tail to sniff between junk. Very sharp seperation. Feels even tighter in width over most of the coil's field than stock. More stabile running over iron or bad ground. Without the coil cover using spray on liner it's lighter than stock. Sensitive to even tiny targets.

If your soil is lower in minerals I'm sure it would be deeper than stock. Strange thing is my beaches are high mineral yet this coil got much deeper than stock. Why it wouldn't on land in my soil is a mystery. Beyond all the above points it's an improvement in all aspects over the stock coil except the land depth thing for me in my soil. Seperation is better left/right wise then stock but of course not length wise. The coil seems to love coins on end.

If coverage is primary on the beach or open field hunting for relics this coil is the best choice, and it may very well get deeper or at least match the stock coil in depth in your soil. Not that it's depth on land wasn't stellar for me, just pretty sure it wasn't quite as deep or deeper than stock in my soil.

All the above positive things can be said for the 12x10, and this coil seems deeper than stock so far for me in my soil...probably because it see's less groung matrix. In fact, I think it sees less ground than the stock coil because it's left/right field is even tighter. Very sharp. For that reason if say you find a 10" coil does not give you more depth than an 8" coil in your soil due to ground minerals, you might find the 12x10 will show an improvement in depth where a 10" or say the S-12 will not. Coverage is still a nice improvement over stock for covering large areas. It's lighter than the S-12 or stock coil without the coil cover. This coil also loves coins on edge, runs more stabile then stock, and so on. The tones seem sharper/more crisp and the machine feels faster with a 12x10.

 

[Critterhunter]

Bumping this thread up too.