Anyone using the D2 10" coil ?

[GroundScanner]

I thing a DD coil is better for my soil. Anyone using the D2 10" coil, is it getting good depth? My AT-pro GB's at 87. So I would say the MXT would also be up there. I have never used the D2 coil. I would like to hear others who has tried it and what you think. Thank, GS

 

[DonM]

I just ordered one for my MXT Pro myself...if you Google "MXT and D2 coil" - you will find a few comments on the various forums from people who have one - most people seem satisfied with its performance based on the comments that I have read.

 

[John (Ma)]

I swear by the D2 and is my primary coil except for the occasional 5.3 in thr heavy iron. D2 is excellent all around with good depth.

 

[Monte]

I thing a DD coil is better for my soil.

What makes you think DD would be better than a Concentric of comparable size? I read a lot of forum posts where people claim a Concentric works better, but they haven't used a Double-D, and equally where a fan of DD's claims them to be tops, but they haven't seriously worked a Concentric against them.

My comments are almost always based on personal in-the-field comparisons, and trust me, I have used MANY 10" D2 DD coils. I worked with a prototype, I got one when released, one came on my original Vision, and then I had a replacement for that coil, and another new one was on my second Vision, and they came with a V3 and V3i, plus I had one on an MXT All-Pro. I have used it on a Vision, V3, V3i, VX3, MXT Pro and MXT All-Pro and MX5. I hunt in 'bad ground' 90+% of the time.

Picking a search coil to work well in any particular soil make-up must also include the detector make and model it is used on, the settings chosen, and the type of site hunted, to include typical desired targets you are after, and we can't forget to factor in the amounts and placement [size=small](scattered or dense and close)[/size] of ferrous and non-ferrous trash.

Anyone using the D2 10" coil, is it getting good depth?

As described, yes, I have used it. Used it a lot in doing searches and in conducting side-by-side comparisons. A lot depends on what a person considers 'depth' to be, but for me and my hunting needs and site choices, it got 'OK' depth, for what it is, but nothing to write home about. When I hunted open areas I generally got a little better depth on coin-sized targets using a 950 Concentric coil, and over the past 13 months the 9" spider Concentric coil.

I haven't really found it to do much for me compared with my 6½" Concentric coil either [size=small](the 5.3 Eclipse)[/size] when both coils were used on the same detector. The 10" D2 DD is the stock coil on the top-of-the-line V3i. I spoke with a White's engineer who gets out detecting a LOT and was very involved on working up some of the custom programs on the V3i. He hunts with a friend who also uses a V3i, and they search many older places, such as old university campus' sites, etc., and I asked him a year or two ago about how the two of them did overall.

Quite often they might be close enough to check the other's located find prior to target recovery, and in the long run they both find about the same number of older coins, and from about the same depths, using about the same custom programs. In short, there's very little difference in depth of detection and good target recoveries between them. He used the 10" D2 DD coil and his friend used the 6½" Concentric coil.

My AT-pro GB's at 87.

Okay, but the Garrett AT Pro, the one I had to evaluate, tended to produce a slightly higher Ground Phase read-out than my MXT Pro. You have the MXT Pro, so what Ground Phase does it read in the same area as your AT Pro?

So I would say the MXT would also be up there.

Kind of a moot point, really, because the best way to know what coil will provide the best in-the-field performance with a detector we have is to actually get the coils in question, then have an open mind and evaluate them all with ample time afield for comparison

I have never used the D2 coil. I would like to hear others who has tried it and what you think. Thank, GS

I have used it, and what do I think of it? Overall I was not impressed with the performance for me, my detectors of choice, or in the types of sites I chose to hunt. Depth wasn't all that exciting and no improvement for me. Target ID and VDI read-outs were usually a little more random or sporadic, typical of most DD coils compared with Concentrics. Also, typical of most DD coil performance compared with similar-size Concentric coils, the DD's had more difficulty rejecting unwanted ferrous-based junk that a Concentric coil can usually handle more cleanly.

Therefore, I don't have a 10" D2 DD coil in my personal search coil battery, and, if I did, I would offer to send it to you to evaluate for yourself. I was fortunate and simply unloaded that poor performance coil for me and the sites I prefer to search.

Monte

 

[plidn1]

You just posted you are having problems ground balancing an automatic ground balancing detector and you're worried about changing coils for depth?
I suggest you start learning how to use your detector first before worrying about depth.
And read the manual 6 times cover to cover.

 

[plidn1]

I just saw one of your previous post that said you have an 8x6 SEF and a 5.3 eclipse. Those to coils are the only ones you will ever need, in any ground.
They are the best performers you could put on an MXT.

 

[GroundScanner]

Let me say that I had used the D2 coil on the V3i a few times. Then took it off and never put it back on. I bought the 8x6 coil for the V3i but always thought it wasn't working to the full capacity because it wasn't V-Rated. So I took it off and put the Whites 5.3 Eclipse on . I have not used the V3i much but will say I felt better with the 5.3 coil on and left it on. Now I have the 8x6 coil on my MXT-Pro. Now I have only been out just seeing what the MXT sounds like in the ground and seeing what target I will be retrieving in the spring. But also when I am done with working the 8x6 , I will put the 5.3 on the MXT and see if those targets I detected with the 8x6 are as good, better or worse. I started metal detecting with a DD coil and I liked it. I tried a Conc. and wasn't to me as good. But I will say I liked it on the V3i. Now I was told a DD coil works better in bad ground . At my home #s for ground balance runs 85 to 93 . Some places in the high 70s and low 80s. But not to many. GS

 

[GroundScanner]

I missed placed the manual and at the time just wanted to run out and try this unit. But now I ground balancing is very easy. GS

 

[Aarong81]

I used the 950 coil in my small yard and "cleaned out" all the good target signals I could find. Then after repeated searches of not finding new targets I put the D2 coil on my MXT Pro and found old wheats, a couple V nickels, and 2 silver dimes. The size of the coil is only a small part of the equation and both of these coils are within a 1/2" in size. Also, these very good targets were not very deep. There are a couple reasons why a concentric coil is nearly blind to these shallow targets, including silver dimes. One reason the concentric coil missed these targets is because there were several trash items close to them, where can you hunt where this is NOT the case??? Another reason that I noticed while digging these targets is that there were large rusted pieces of iron in the holes. I would call those 'trash' but it is more specific than a trash target. Large pieces of iron would normally show as iron and you can easily move on and not dig. But the D2 allowed me to SEE the iron.......AND the good target right next to it. You CANNOT do that with a concentric coil. If you could, there would be little reason for other coil designs. I'm still shocked that a moderately sized coil, the 950, missed so many shallow targets.
The D2 just happened to be what found those targets missed by the 950 but I am SURE that many DD's would have also been well suited in the same situation. The D2 just happens to also work well as a general purpose coil so that is why I use it as my main coil. The 5.3 is better in highly mineralized soil.
The biggest complaint I have about the D2 is that it, along with most DD's, will show bottlecaps very high on the VDI scale. Aside from digging 'extra' targets, the D2 doesn't miss much. That is the reason we look for a better coil, isn't it? VDI's not being accurate is a moot point if you dig most 'good targets' to begin with. If you are in a good area and not digging bottlecap signals, you are missing more than bottlecaps. Does it find more than a similar sized concentric? Absolutely. Does it always tell the truth about the target before digging? No. Does a concentric even see some of those targets the D2 lies about? nope. I use the coil that sees the most good targets and it happens to exaggerate about bottlecaps. A worthwhile tradeoff if you get to dig the GOOD targets that a concentric coil user won't ever know is there. The past 4 decades of detectorists using concentric coils have dug most of the easy targets. I wish a concentric coil would find those difficult targets but at least DD coils can, even if they are dishonost at times. Besides, if the area is littered with bottlecaps, you really need to dig and remove them so you can detect deeper below them.

 

[GroundScanner]

Thanks Aarong81 for your info. GS

 

[Monte]

For readers, and you, this is not meant to be argumentative, simply another view of why we each choose to use what we feel works for us and our experiences with detectors and coils we have used.

I used the 950 coil in my small yard and "cleaned out" all the good target signals I could find. Then after repeated searches of not finding new targets I put the D2 coil on my MXT Pro and found old wheats, a couple V nickels, and 2 silver dimes.

Yes, that can happen, and usually will ... even if you used a different detector with the 950, or you used a different search coil than the 950 to include another Concentric coil. You hunt behind someone else using any detector and any coil, even both the same, and you find stuff the other one didn't. Then turn around and hunt back another direction with you leading the way and the other person finds stuff you somehow missed. It happens, and it happens all the time.

Sweep speed, coil presentation, overlapping efficiency, settings used, soil moisture or dryness and to what depths, and the particular search coil used can all make a difference between visits over the same general area. That's why many of us come to appreciate a particular make and model detector or type and size search coil for our chosen places to search.

The size of the coil is only a small part of the equation and both of these coils are within a 1/2" in size.

Physical size sometimes does matter, like preferring a smaller-size search coil for trashier places and a larger size coil for bigger-size targets, etc. In my case I am usually searching trashier sites, and often they might also be brushy or have building rubble to add bigger junk to deal with. By 'trashier' I am referring to both ferrous-based junk [size=small](nails, tin, bottle caps, washers, wire, etc.)[/size] and non-ferrous [size=small](various sizes of clipped aluminum, small zinc caps, rivets and rivet parts, larger zinc canning jar lids, and so much it's unlistable)[/size].

I have compared 4½" diameter Concentric coils to slightly sub-5" Double-D coils, and round 6" diameter Double-D coil to round 6½" diameter Concentric coil, or even same size/same manufacturer 6" or 7" Concentric and DD's, and in almost every instance, certainly the vast majority, the round Concentric coils out-performed the round Double-D designs. At one site where I have exclusive access by a project foreman, I worked it sometimes for a couple of hours in a morning, mid-day or late afternoon, and on other days I could spent a full eight hours or more hunting it.

Three times I invited friends who are also avid detectorists to join me, partly for the fun of it, and partly to use an assortment of search coils I was evaluating on various detectors. At the time we were using White's XLT's, XL Pro's and Classic ID & IDX Pros, plus the MXT, M6, MXT Pro and the Vision then Spectra V3 models, plus a Teknetics Omega. We used both the metal detector manufacturer's Concentric and Double-D coils as well as some aftermarket coils, most of which were DD's.

In conclusion, the four of us were all in agreement that overall the Concentric coils worked better, provided cleaner hits in trashier areas, produced tighter TID/VDI read-outs as well as more accurate readings, had a little edge in depth of detection, and either confirmed our prior coil choice decisions or convinced one of the four of us to question their coil choices and add one or two Concentric coils to their arsenal.

Were all of the DD search coils terrible? No, but as a whole they were less impressive. Of them all, the Double-D coils that we [size=small](as a foursome of opinion gatherers working the same site on several long summer days and using the same detectors and coils)[/size] did like were the 5" DD from Teknetics, but one reason is that there was no similar-size Concentric to compare with on that brand/model.

We also like the Detech 5" DD on the White's models for the nastiest of trash conditions where it had a slight edge on the 6" DD Detech and 6½" Concentric White's coils. A slight edge, whereas we all agreed the 6½" Concentric White's coil surpassed the overall performance of the 6" DD coil. Of all the larger-size coils used, anything over 8" in diameter, we were 'OK' with the elliptical 5½X9¾ Concentric on the Teknetics Omega, but liked the round 8" Concentric better.

We agreed that the 950 was kind of "on the fence" between being okay or so-so. The 10" round Detech coil we used was better than the other larger-sized coils, and the worst of them used was the round 10" D2 DD. Other than the 5" DD coils from Teknetics and Detech, the only Double-D that any of us liked was the 6X8 SEF coil and we agreed, as a whole, that if we were to pick a DD coil to use for most of the similar old sites we hunt, it would be one of the 5" or the 6X8 SEF. In conclusion, however, other than the 5" DD's, all of us favored the overall performance of Concentric coils in the 6", 6½" , 7" or 8" diameter sizes. We didn't have the newer 9" spider coil available at the time, which is close to the performance of the 950, but ...

Also, these very good targets were not very deep. There are a couple reasons why a concentric coil is nearly blind to these shallow targets, including silver dimes.

I hunt mostly older sites but plenty of newer places, and the bulk of the coins I find are from surface to 4" deep. Recovering to 5" or rarely ±6" happens, and sites are quite littered, but overall a Concentric coil works splendidly for me on most of my detectors of choice. I can assure you I haven't found a Concentric coil to be "blind to shallow targets" other than times where there is some closely associated junk that could mask a good target, but the same junk and same Discrimination settings will impact a DD coil just as well, and often they can be more hindered than a Concentric coil. Size and type of design do make a difference.

One reason the concentric coil missed these targets is because there were several trash items close to them, where can you hunt where this is NOT the case???

Correct, most, or certainly very many, of the types of sites we chose to hunt are littered. More littered today than they were in the early era of the recreational metal detecting hobby, and with higher-conductive junk than before, and more of it is non-ferrous, too. Any type of search coil can be challenged by closely associated trash, but with the right detector and settings and coil choice, I don't really have any problems with good Concentric search coils missing targets, in a mix, more than a DD type coil.

Another reason that I noticed while digging these targets is that there were large rusted pieces of iron in the holes. I would call those 'trash' but it is more specific than a trash target. Large pieces of iron would normally show as iron and you can easily move on and not dig. But the D2 allowed me to SEE the iron.......AND the good target right next to it.

I pick good targets from iron, even large iron, using Concentric coils, but that just goes to show that we can all find a coil or two or a make and model of detector or two that will serve use well, and satisfy us, with one type of coil where another type pleases somebody else.

I do own and use some detectors [size=small](4, my old Compass T/R Coin Hustler and 99B, White's MXT All-Pro, and Nokta FORS CoRe)[/size] that came with a Double-D coil, and I do use a factory DD coil on 3 of those 4 models [size=small](the old Compass T/R units and new Nokta FORS CoRe)[/size] but only Concentric 6½" and 9" spider Concentric coils on the MXT All-Pro. I do own and use a smaller-size DD on a detector that came with, and usually uses, a Concentric coil [size=small](Teknetics Omgea)[/size] when I am in a very dense trash environment.

You CANNOT do that with a concentric coil. If you could, there would be little reason for other coil designs.

Well, I and others CAN do that with Concentric coils, and I don't mind if there are other coil designs [size=small](DD)[/size] for folks to pick from because we all have our preferences, and mine are based on five decades of in-the-field experience with all of them.

I'm still shocked that a moderately sized coil, the 950, missed so many shallow targets.

I'm not, but I consider the 950 to be a bigger sized coil by just a little bit. I also seldom use a 950 coil. The one for my XLT sits dormant on a shelf at home and I don't even take it along in my accessory search coil bag. I don't use the stock 950 on a VX3, either. Most of the time I am working a smaller-size search coil in the 6" to 7" range, except for an 8" to 9" Concentric in open areas.

If my detector/coil choice is for a Double-D design it is the 5" on an Omega or the 4.[size=small]7[/size]X5.[size=small]2[/size] or 7X11.[size=small]2[/size] on the Nokta FORS CoRe. On the rare occasions when I am after something larger in size, I still have a 12" Concentric at the ready for the MXT All-Pro or 13.[size=small]3[/size]X15.[size=small]5[/size] DD for the FORS CoRe.

I prefer smaller-than-stock coils most of the time, and if I do my part to work the search coil methodically at a proper sweep speed, I am confident in the efficiency of what I put in my hand for any given site.

The D2 just happened to be what found those targets missed by the 950 but I am SURE that many DD's would have also been well suited in the same situation.

I am glad you found stuff with the 10" D2 coil that you had missed. Congrats! But I am also sure that you could have used a different Concentric coil and also had some successful searches.

The D2 just happens to also work well as a general purpose coil so that is why I use it as my main coil.

And I am glad it works for you and you are comfortable with it as a main-use search coil. That's what everyone should do in order to be more relaxed and feel more comfortable about their detector and coil choices as it can lead to better results afield. But it doesn't mean those are the detector and or coil choices for others.

The 5.3 is better in highly mineralized soil.

No argument there. It's also better in trashier places.

The biggest complaint I have about the D2 is that it, along with most DD's, will show bottlecaps very high on the VDI scale.

Yep, in total agreement because that is one of the weaknesses of the Double-D coil design, being unable to deal with a lot of ferrous type trash targets. Bottle caps, due to metal make-up AND the way man shaped some magnetic-based metal to enhance its conductivity, are a problem.

Aside from digging 'extra' targets, the D2 doesn't miss much. That is the reason we look for a better coil, isn't it?

Exactly, and I think everyone ought to try an assortment of search coils in a variety of site environments to select the ones that work best for them to have a desired 'standard' size coil and 'smaller-than-stock' sized coil.

VDI's not being accurate is a moot point if you dig most 'good targets' to begin with. If you are in a good area and not digging bottlecap signals, you are missing more than bottlecaps.

100% correct. If a site is a challenge with a lot of trash, especially ferrous types or copy-cat conductive trash that reads like coins, trade tokens, buttons, jewelry, etc., you have to recover the unwanted stuff to get all the desired targets.

Does it find more than a similar sized concentric? Absolutely.

Debatable, but the only way to know for sure is use more than one detector and try several settings, and maybe do some side-by-side work with both coils at the same time and in the same conditions. It also can help if two or more people get together to evaluate detectors and coils, and try more challenging scenarios then compare their results. I use Concentrics that I could say 'Absolutely' out-perform similar-sized DD's. We all get to make our choices and live with them.

Does it always tell the truth about the target before digging? No.

None of them do. All visual TID and VDI read-outs are only a 'best guess' made my a detector. We have to recover a target and take a look at it in-hand to determine if it is a keeper or not.

Does a concentric even see some of those targets the D2 lies about? nope.

??? The DD's can lie or fib about a targets identity, and Concentric can do it, also.

I use the coil that sees the most good targets and it happens to exaggerate about bottlecaps. A worthwhile tradeoff if you get to dig the GOOD targets that a concentric coil user won't ever know is there.

??? I find bottle caps with a Concentric. They can give a good signal, too, or at least a tell-tale signal, it's just that most DD's give a worse signal on them. I can use a Concentric or DD coil and 'classify' most bottle caps which are usually in the surface to 3" depth range, but it is easier with a Concentric coil.

The past 4 decades of detectorists using concentric coils have dug most of the easy targets.

Past four decades? Go back to 1974/75, four decades ago, and ask a manufacturer if they used a Double-D search coil or Concentric search coil. Most of them would scratch their heads because a 'Concentric" coil, as we know it, wasn't in popular use then as were the DD coils. Compass started the popular use of a DD coil for modern hobby detectors with their Yukon T/R's in '71, while other detector makers were using other coil configurations, such as a triplet or other designs, until they improved the coil types that eventually became a Concentric coil as in use today.

Matter of fact, 4-decades ago, quite a few people were still using a mono coil BFO and basic T/R's, and until they improved the search coil designs by the latter '70s [size=small](along with improved or advanced detector designs)[/size]. I was still finding a lot of the available and plentiful coins working a conventional Compass T/R with a Double-D coil. Back then, good targets were easier to find because they were plentiful in ratio to the smaller amount of trash, and most of the annoying trash then was small iron, like nails or hair pins, or small non-iron such as foil. Today, and over the past thirty years, we haven't had the amount of coin usage or coin loss, but we have had an increase in the amount of discarded junk, and a LOT of it is a higher-conductive type of non-ferrous trash.

I wish a concentric coil would find those difficult targets but at least DD coils can, even if they are dishonost at times. Besides, if the area is littered with bottlecaps, you really need to dig and remove them so you can detect deeper below them.

In my experiences, and with the coil and detectors I use, Concentric coils DO find the small and difficult items. I agree with you, however, that if a site is littered, bottle caps or other trash, we need to recover and remove it if we want to get all of the desired finds that might be there. It's all a matter of basics.

Monte

 

[PSS1963]

Monte, as usual makes some valid points - however - most of these comparisons end up being apples to oranges and consequently subjective for the simple fact that as soon as you recover targets from a site, it is no longer the same site but a new site with new targets to find. The only way (aside from a test garden) to make scientifically valid comparisons of machines, coils and settings is to search a given patch of ground and mark targets without recovering them, then re-search the same ground with a different configuration and note the responses for that one - otherwise the first pass generally grabs the low-hanging fruit and subsequent ones have to settle for the more difficult or "iffy" targets. This is of course hard to do on public lands and easiest to do on private land where you have exclusive access.

 

[taterbill]

n/t

 

[Aarong81]

All good points, Monte. I believe that your preference of 5, 6 & 7 inch concentrics lessons the need for any other coil type. For example, I missed targets with my 950 that you would've found with the 5.3 coil. The 5.3 can edge against iron and see the good targets that the 950 cannot due to target overlap. I started out detecting thinking that I had to go deeper to find stuff that previous detectorists missed due to them not being able to detect as deep with old technology. I now know that is a stretch and going bigger/deeper is not a reliable payoff. But that train of thought probably went through my mind as I invested in the D2. I can attest that the D2 has not "gone deeper" than a similar sized concentric but when compared directly to a similar sized concentric it can detect closer to junk when masking is a problem. However, A smaller concentric(5.3) can do the same thing. What a 950 cannot see, perhaps the D2 can. The 5.3 will see it as well but there are draw backs with leaving a small coil mounted on a regular basis. The D2 fills that need of detecting close to junk....and the need for ground coverage.

I havn't seen the situation where the 5.3 could detect a given target that the D2 could not. False VDI's? Yes, but not important unless you are cherry picking targets or in a public park digging precise VDI's. More ground coverage: Yes. Less stable than the 5.3(edit: as well as 950)? Yes, and hasn't even been mentioned yet.

Pros and Cons will be applied to every coil selection. You will lose stabilty, and VDI accuracy with the D2. You will gain ground coverage and the abilty to detect closer to junk when compared to the SAME size concentric coil. That does not meen it detects closer to junk than the 5.3 as it is NOT a like size coil, any small coil can detect closer to junk than a larger coil.

Of all the targets I have dug in my yard, using multiple coils, I would wager that the 5.3 would've been able to find ALL of them.....with VERY little doubt. Why even use another coil? I think it would require 2 or 3 coil styles/designs to thoroughly clean out a given area. Most of us don't clean out an area and only get to detect it a few times before finding new ground. Those few times beckon us to use the coil that will get the most targets out of the ground on those first few visits. Ground coverage is very important UNLESS you are going to clean out the area completely and invest all summer in a small area. Detecting close to junk targets without masking is important, otherwise you are wasting time and missing good targets. Does a small concentric cover both of those needs? Those last two reasons are why I like a moderate sized DD instead of a small concentric. Again, that small concentric WILL find the same targets but coverage is an issue when time is valuable.

 

[Aarong81]

This chart is just a visual representation of my comparison between these 4 coils. It does not suggest an exact depth, or other statistic, but only a comparison to the other coils in a percentage scale 'per se'. It shows the winner and loser of each statistic and every coil will differ with some advantage along with a disadvantage(pros and cons). This chart may even be wrong but this is my comparison.