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  1. This post was a response buried deep in a thread on the Equinox Forum, but got long enough on a subject I think about a lot, that it deserved its own thread. Here you go. I find the whole George Payne way of conceptualizing things to be rather out of date myself. That was back in the day when only one thing mattered - detecting coins. Silver coins in particular. So he was looking at frequency, and most importantly, coin size targets. If you do that, fix target size, you get the false idea that frequency corresponds to type of metal. Nickels respond here. Gold coins here. Copper coins here. And the biggie, silver coins here. That's how the first coin discriminators were conceived. But it has also lead to this mythology that frequency corresponds to metals. Gold is high frequency, silver low frequency. No, it's not. There is no correlation between frequency and type of metal if you do not fix the size at some artificial limit. In fact, gold ranges from ground readings all the way to so-called silver readings. If you fix the metal type, frequency corresponds to size. Low frequency big gold, high frequency small gold. There was also ground to deal with, and ground reacts less well at low frequencies, so a double bonus for silver hunters. You might think it is low frequency working better with silver. But you might also think of it in terms of the detector simply being better able to see the silver, for not seeing the ground. It's all about conceptualization, and you can conceive of the same thing from different angles. I consider the old George Payne way of looking at things as obsolete from my perspective. It really was only something that worked well in the United States, and only because of an accident in our coin size and metal types. It allowed a scale to be created that worked well with silver coins and nickels, while knocking out a lot of trash items. In most other countries, our target id scale is worthless because their coins do not fit our classic scale. I detect for gold. I think in different terms entirely. For me frequency does two opposing things. Higher frequency is better for small targets. Small gold, small silver, small copper..... small stuff. But high frequencies also enhance ground, and especially, hot rock responses. The two effects offset each other, and can reverse things if ground is severe enough. This also totally applies not to nugget hunters like myself, but almost anybody hunting coins and relics under any situation but the classic U.S. silver coin regime. Let me explain. So I want to find gold nuggets. I must first think about the nugget size that I am looking for. I can look for the more common small gold, or the rarer large gold. If I want tiny gold, I usually want a high frequency detector, the higher the better. Now, here is the kicker. High frequency does just fine on large gold also. In fact, high frequency just detects well on everything - in the air. So air test a Gold Bug 2 on things, and it is amazing. Unfortunately, the high frequency also "lights up" the ground to an amazing degree, and it is hard to get good depth on anything at very high frequencies. The signal attenuates rapidly in the ground, and the worse the ground is (more magnetite in general), the faster the depth drops off. Hot rocks that never responded at low frequencies are now everywhere at high frequencies. Lower frequency starts looking better not just because it does better on large targets, but just as much because it is less reactive to the ground. The 71 kHz Gold Bug 2 is an amazing detector. I can find pinhead gold with it. The big caveat is that in most nugget ground it has low penetration, and is very poor on large nuggets at depth. Not because it air tests poorly on large gold, but because the ground sucks up the signal. 71 kHz is great for small gold, and even large gold in the mildest soils, but in bad ground it has poor depth, and makes hot rocks a real issue. If I am looking for large gold at depth, I might very well use a lower frequency VLF in the old days, just as much because it is responding less to the ground as anything else, allowing large gold to be more easily found at depth. For my purposes, a PI detector for a long time was just a high power, super low frequency detector. Huge punch on large gold, with minimal ground response. So PI took over early on from the VLF low frequency, large nugget detectors of the time. I mentioned relic detecting and coins in other countries. If you detect Europe, our U.S. coin scale is garbage. It's not "low frequency = silver." Over there silver can be all over the target id map. Huge silver coins. Or tiny silver coins. Or small coins hammered thin as foil. Or those hammered coins cut to make change. Silver under those circumstances occurs anywhere on your target id scale from ground to the highest reading, 0 to 100. It all just depends on the size, with a little ground effect tossed in to drag things down. So in Europe, if you want to chase tiny silver cut coins, or very small gold coins, higher frequencies work well, whether it is gold or silver. The metal does not matter. It is size that matters. Relic hunters see the very same thing. High frequencies find the small bits, regardless of what they are - worst fact being tiny ferrous. I long ago tossed the frequency and metal thing in my garbage can. Here is my reality. High frequency will help me with smaller targets, but also make dealing with the ground harder. Low frequencies simply have less ground and hot rock response, and also less tiny trash stuff response, making them better if I want want to focus on larger targets, like coins or rings. In my lifetime experience there is a crossover point for gold, and going too high enhances tiny gold nuggets, but also loses depth due to ground issues. A sweet spot develops around 50 kHz, which White's chose ages ago in the Goldmaster II, as being great for small gold nuggets, while still retaining punch in bad ground on larger gold nuggets. Minelab rediscovered this with the Gold Monster, and went with 45 kHz for this very reason. They found pushing high did better on tiny stuff, but the cost in larger heavier gold was not worth it to serious nugget hunters in bad Australian type ground. If I was hunting tailing piles for ounce type gold nuggets, it is hard to beat a 15 kHz type detector, just like that ancient 15 kHz Garrett Groundhog circuit, that was at the time a high frequency, but in retrospect was a great large nugget lower frequency. The White's MXT at 13 kHz is superb on large nuggets in trashy locations. If you are in Europe, that 15 kHz sweet spot applied for a long time, but more recently people have discovered the benefits of higher frequencies on these tiny cut silver and small gold coin finds. Pulse Induction did serve as super low frequency for a long time. You gave up small gold to get big gold as deep as possible. The lack of ground response allows use of extra large coils. It is interesting to me that as newer PI detectors are pushed to get more sensitive to small gold, that ground and hot rocks have also become more problematic. The newest PI nugget hunters suffer from hot rock responses you never saw on the old PI models. PI is getting more like VLF over time. So Billy, does Minelab put all this in Multi-IQ processing? Of course. But not in the way you think. They think more like me. It's every bit as much about ground, and saltwater, and even EMI, and what you do not want to detect, more so than metal types. A primary choice is saltwater - that forces a low frequency mix simply to avoid the salt response. Which, as I seem to have explained to beach guys a million times, also knocks out small gold responses. For large coin detecting a lower frequency mix gives clean responses on larger targets like U.S. coins and rings, while getting less ground response, fewer hot rocks, and far less tiny trash signaling. It is not targeting silver coins per se, just larger stuff. For tiny items, gold nuggets, small hammered silver coins, a higher frequency mix works well, but you will deal with more ground and hot rock response, more tiny trash. Forget metal type. Think size and ground, including saltwater, and hot rocks. As you increase frequency, everything responds better, and small items that respond poorly or not at all at low frequencies will do better. Ground, saltwater, and hot rock signals also increase with frequency. The first cut off is at saltwater. To work there, you must have a lower frequency mix to eliminate salt signal, and you lose all tiny stuff as well, tiny aluminum, tiny gold. This can also do very well on large targets in any ground. The teens are really nice for general detecting, right on the edge of the salt range. 12 kHz - 15 kHz hits really well on most desired detecting targets, while not being overly sensitive to ground and the tiniest trash targets. 40 - 50 kHz is a sweet spot for gold nuggets and all really small targets, like the smallest cut silver coin, targeting the sub-gram range kind of stuff with some alleviation of ground and hot rock issues that develop at extreme frequencies. You get up above 50 kHz and you really are just surface skimming for the tiniest bits. Depth just drops off rapidly due to the ground, and so this is specialty range for the smallest targets. Multifrequency changes none of this, and making a machine that found everything best at all frequencies just gives you a detector that reacts to everything and finds nothing. It is about picking a few divergent frequencies that when differentials are applied, can add extra target information. This is as much about ground as anything else. The classic is the salt beach, where you want to notch out both salt response and ground response. Single frequency can't get you there except in crudest form, eliminating both, while losing a lot of gold. Using two frequencies lets you notch back in some gold jewelry missed by eliminating both ground and salt with a single frequency. Looking at two frequencies that are close together is a waste of time and processing power. The target and ground response is the same. But pick two very divergent frequencies, and you will see differences in target response and ground response. This whole idea of having a detector look at and analyze 100 frequencies simply makes no sense, and reveals the nonsense we have been fed for ages about more frequencies being better. Again, there are only a handful of gross frequency ranges that really matter. Under 10 kHz = find U.S. large coins well, minimal small trash and ground responses, few hot rocks. Call this Park Mode, with a special subset that tunes out salt, called Beach Mode 15 kHz plus or minus, great on a large range of small to large targets, while still not being overly sensitive to ground and very tiny trash. Call this Field Mode. This is an excellent all around compromise mode between low and high. 40 - 50 kHz is great for sub-gram targets, but will make dealing with ground and tiny trash problematic. Let's call this a Gold Mode. 70 - 80 kHz is basically surface skimming for pinheads, max hot rock and tiny trash response. Pinhead Mode? A niche area for sure. Four basic options, and really three, since the highest is very niche. It is also comparing results in these three or four options that give you the most bang for the buck in multi. They diverge enough to provide the basis for good differential algorithms. Again, multifrequency really just adds better ground and target id capability for cleaner, more accurate responses across the board. It's not some magic about finding all targets best at all frequencies by lumping them all together. Most frequency discussions simply miss the reality of what is going on, and what is being achieved by going multifrequency. I will say it one last time. Think of frequency, whether single frequency, or a mix of frequencies, in terms of the desired target size, offset by the added ground/salt response. Think of the target id scale as a size scale, low numbers are small targets, high numbers large targets. Think less about it being an indication of type of metal. Aluminum responds anywhere on the scale. So does gold, lead, silver, copper. Small foil a low single digit, and aluminum can like a silver quarter. Pick your frequency mix and your target id numbers to match the size of the targets you are seeking, and life will get easier. And quit thinking of multifrequency in terms of finding more targets better the more frequencies you use. Nonsense, just marketing nonsense. The White’s chart below kind of says it all. I’d certainly be picking a high frequency VLF for the tiny gold. But $20 gold coins? Any good detector is going to work, and I’d be far more likely to go 15 kHz or lower.
  2. Concerning @calabash digger's video where he talks about the Legend and it's lack of an iron bias setting. Does a SMF detector necessarily require an iron bias setting? or is that a facet of the unique signal processing that the Equinox 800 uses. I mean, as far as I can tell the Deus II does not have an iron bias setting nor equivalent setting, but nobody seems to be criticizing that detector for it. The Silencer setting seems to be about eliminating iron falsing, but seems to be fundamentally different from iron bias. Calabash also say that an incorrect iron bias setting could lead to you digging iron all day. I run F2 of zero on my Equinox and I still essentially dig no iron unless I am intentionally going after very deep, iffy signals (which I know have a high probability of being iron before digging). On F2 of zero, it's still incredibly obvious what is iron, but it does allow it to false through more into non-iron IDs (I use full tones and have noticed that the lower F2 setting the higher the iron false will peak in the target ids). I do see the value in an Iron Bias setting as Calabash said, for cherry picking. When I am scouting a new location, I run high iron bias while I am looking for indicator targets (here, there are old large copper coins from the 1600-1700s that ring up at 30+ that are impossible to miss and indicate to you that you are on a good patch of old ground) and it speeds up the process by decreasing the number of signals to consider. To me, it seems that the Legend's iron indicator takes the place of the Equinox's Iron Bias setting. You can either hide the iron indicator and then use an algorithm to sort (Minelab's iron bias approach) targets using that information, or you can give the user the graph and allow them to make the iron bias call themselves. The former seems more user friendly, but the latter seems more powerful. It is true that the Legend's iron indicator stops working at depth, but in my experience so does the Equinox 800's iron bias setting.
  3. Every time we get new detectors for the beach, we get the same question. "Will it find thin gold chains better?" It comes up so often I finally dug up an old post I can just point to whenever it comes up. Here you go. Gold Chains and Other Small Gold In Saltwater Here is a similar question that comes up a lot: Why Won't My Detector Find That Gold Chain? There seems to be a thought process that thinks somehow multifrequency overrides basic laws of physics, that some magic new processing is going to fix the issue. No. Not as long as conductivity is the measure. Once you understand this, you stop asking the question. Hopefully the article helps out with that.
  4. in this video we can see that the main transmitted signal is the same - Multi signal Equinox Park/Field/Gold = Deus-2 pr.1/2/3/4/8/12 - Equinox Beach and Deus-2 pr.5/9/11 signals are slightly different, but the upper frequencies are the same 24кГц - Equinox does not have a low-frequency signal, like deus-2 Deep and Diving program (Pr. 6/10)
  5. Minelab chose to split modes (eg Park1 and 2) on the equinox to favor a weighted end of its available frequencies. The Deus 2’s “general” mode for example appears to be equally weighted (or not weighted at all) through all its available frequencies. I’m not on the same level as a lot of you folks on how the magic works in these detectors, but I am a curious soul. So, I won’t ask how either machine processes information, but Id like to ask why Minelab would choose to split and weight modes as opposed to processing the 5-40khz with no weight in each available mode?
  6. https://www.theguardian.com/world/2022/jan/12/landmine-hunting-hero-rat-dies-in-cambodia-after-stellar-career?CMP=Share_iOSApp_Other
  7. Does that make any sense? I don’t think we have seen multi freq detector engineered like this. Assuming what’s in the manual is the truth.
  8. If Dimitar did get his patents which were pending sorted does the XP D2 infringe on any of these ? it seems that the performance increases of the D2 over existing units is because of the separate salt balance that it has like the Tarsacci MDT8000 unit uses. Maybe Dimitar only got the patent (if still not pending) for single frequency separate salt balance (Mixed Domain?) and XP have filed for the multi frequency patent? or is Mixed Domain something else other than just separate salt balance ?
  9. Here’s a topic for all you “Rocket Scientists” out there (and anyone else who’d like to chime in). I was having a discussion with another dealer. He felt that single frequency worked better because there’s a certain amount of performance loss with Multi. I was always of the opinion that Multi-Frequency was the best for most types of Metal Detecting. It allows you to hit ALL the targets that react better to certain kHz. Here’s an example from another hobby of mine (most of us have more than one). I shoot muzzle loading guns. The “Round Ball” type projectile that was used for hundreds of years performs best when shot out of a rifled barrel with a slow twist. Twist refers to the how many inches of flight it (the projectile) takes to make one revolution. The conical bullet came out during the Civil War and requires a faster twist. For modern muzzle loading rifles a slow twist would be 1 turn in 56, 60, 66, 70, etc. inches. For conicals, 32, 28, 24, etc. inches. In the 70s, one company came up with the idea of a “Compromise” twist; 1 tun in 48”. That way you only have to buy one gun. You can use Round Balls for Target shooting and Conicals for hunting. It shoots both “well”. Having said all that, does the Single Frequency work better than the Multi? Is there any kind of lack of performance or trade off having them (kHz) work simultaneously? Thanks! Walt
  10. We have the Deus 2 just announced, Nokta/Makro Multi on the way, possibly the next generation Equinox from Minelab, and maybe even another Garrett multifrequency model to follow Apex, all coming in 2022. I guess we should even toss First Texas in there, as they just officially discontinued the CZ-3D, with the possibility something new will replace it soon. If this does not mean we are moving past single frequency, I don’t know what does. Or are we? There will no doubt always be a place for a finely tuned single frequency detector. However, if you consider Deus as selectable frequency, and Equinox as selectable/multi, then very many of us have already moved past a simple single frequency detector as our primary detectors. This is the thread to speculate on what is coming, where we are, and where we are headed. 2022 is shaping up as the year SMF (simultaneous multifrequency) finally takes off for real. In some detectors, it’s just companies chasing the latest marketing catchword. Multifrequency is only as good as the way it is implemented, otherwise we’d all have been swinging White’s DFX ages ago. It’s not enough to make a SMF detector, it also has to have genuine performance advantages. About the only given is that any multifrequency machine will outperform a single frequency on a saltwater beach. The rest, however, is very much up in the air. For some detailed explanation of the technology, and a history of past selectable and simultaneous multifrequency detectors, see my write up on Selectable Frequency And Multiple Frequency Where it all started, Fisher CZ-6 and Minelab Sovereign, both released in 1991. I think Fisher wins claim to being first, since Minelab takes a swipe at them in their Sovereign introduction. Notice how the misdirection on transmitted versus received and processed started on day one. Fisher CZ-6 Quicksilver. The technology: Dual frequency Fourier Domain Signal Analysis. Patented state-of-the-art analog/digital electronics transmit two VLF signals (one 5 kHz, one at 15 kHz) deep into mineralized soil. The receiver circuitry had two ground compensated target signals to analyze, compare and identify. The result? Deeper targets, more accurate target identification. Wet sand is no problem for the CZ-6, it compensates for salt and ground mineralization simultaneously! Source Fisher CZ-6 Datasheet "The Sovereign" is the first of the latest generation of metal detectors from Minelab featuring Minelab's new technology called Broad Band Spectrum or BBS for short. This revolutionary new technology which is unique to Minelab has already been awarded patents in the USA, Canada and Australia and has several pending. Unlike other metal detectors which operate at just one frequency, or even the "newest" two frequency machines, "The Sovereign" actually transmits over a wide spectrum of frequencies. The resulting signal that is received from a target buried in the ground is processed by a microprocessor that removes interference caused by ground mineralization which limits the depth at which targets can be found, and often results in inaccurate target identification. The remaining signal can then be analysed to determine the actual composition of targets even if they are deeply buried, or if the ground is mineralized or salt water is present. Thus it is the only detector that can simultaneously reject both salt and mineralization while at the same time accurately discriminating the target, making it ideal for black sand beaches and many desert areas. In many areas that are highly mineralized and have been heavily searched in the past, "The Sovereign" will prove that many of the valuable targets are still there waiting for a Treasure Hunter with the proper detector to locate them. Source Minelab Sovereign Instruction Manual
  11. Hello everyone. Hope you all had a lovely Christmas. I've been doing pretty well with my nokta makro multi kruzer. I love it. I did some detecting in an old park today and found my first silver content silver. A 1929 Canadian dime. 80 percent silver 20 percent copper. Now I run my machine on 5 khz as this is supposed to give more depth for silver and copper etc I can't for the life of me remember what the dime was ringing in at but it rings it at 73 air tested. My question is it possible for that same dime to ring in at 30 on vdi and then obviously it'll change to 73 once out? I switched to disc at 55 and didn't really get many coins for the rest of the day. Found a 1897 young Vicky large cent that rang in at a choppy 30 to 75 and then 54 out of the ground. They're bronze. So far I've found 8 large cents numerous relics and the silver dime. Pretty happy. I know vdi is just a guide like. I'm thinking I may just dig anything that has a solid tone. I also dug 10 pull tabs and 5 bottle caps today haha
  12. What is the differences between the “range of simultaneous multi frequencies” utilized in both the Equinox 800 detecting modes and the Nokta Makro Legend modes? Here is my attempt to explain my concern: Per the ML Equinox 800 user manual the Equinox provides four (4) detecting modes: Park, Field, Beach, Gold; plus eight (8) profiles divided in two (2) pairs per mode: such as Park 1, Park 2, Field 1, Field 2, etc; and one (1) custom user profile side button. Park 1, Field 1, Beach 1 & Beach 2 are “weighted” on the “lower simultaneous multi frequency range”. Park 2, Field 2, Gold 1 & Gold 2 are “weighted” on “ higher simultaneous multi frequency range. The NM Legend has four (4) detecting modes: Park, Field, Beach (dry & wet) & Goldfield; zero (0) profiles such as Park 1, Park 2, etc; and four (4) user custom modes. All the detecting modes, per NM all modes are optimized for depth. Currently NM has not addressed nor is there a specification “weighing” the range of simultaneous multi frequencies (low, mid, high) utilized in any of the NM Legend’s detecting modes. The YouTube video “Pasture 1” find of a thin coin indicates the “Field mode” may be utilizing a higher SMF range. When the Legend’s user manual is available online perhaps Nokta Makro will explain how simultaneous multi frequencies are utilized or weighed specific to each of the NM Legend four (4) detecting modes. Do the math 4x2 =8; 4x1=4; 4-8= -4. Certainly an answer I will be looking for prior to placing a pre-order or purchase.
  13. I just watched a video of a guy comparing the new legend to the equinox on Monte’s nail board test. Sorry, but I don’t have a link to it, but I think I saw it over on the friendly forum. In the video he is using the nox and says he has the recovery speed set at 8 and sensitivity at 23. Then he also mentions that recovery speed is what’s important on this test, not sensitivity. I have to disagree. Running 23 sense on what is basically an air test with an 11” coil only a few inches above the targets seems like way too much power to me. Monte has confirmed that this test of his was developed from surface finds. So I’m thinking this guy would have gotten better results (with both nox and legend) by lowering the sensitivity dramatically. Like maybe down to 10 or 12 on the nox. Am I correct in my assumptions? I have a site near my house that’s loaded with old iron. Most finds are 3-5” deep or less. I’ve actually compared non ferrous signals with low sensitivity and then bumped the sense up to 20 or so and the signal is more muddled and much more iffy to define than on the lower setting of around 12. I’m just curious why these guys doing the nail board tests aren’t at least trying a lower sensitivity setting?
  14. I haven’t been in the market for a new detector for some time now. The VLF detectors hanging around here all have a fixed preset unknown “recovery speed” and only one detector has the option of changing out one coil with another of different frequency. Imagine my surprised when I read up on “Simultaneous Multi-Frequency”. After learning more about it, what really jumped out to me was the ability to adjust the “recovery speed” and the impact it had on target separation and search depth. Better yet “adjustable recovery speed” was now married to “preset unknown range of simultaneous multi-frequencies”. Could it get any better? What if we woke up Christmas morning to discover somebody wrote a few algorithms allowing us the pick and adjust for a known range simultaneous multi-frequencies (low, mid, high) to go along with our adjustable recovery speeds. We could design your own detecting search modes based on the ground conditions and targets we were actually detecting that moment. Maybe the cat is out of the bag but not in our Christmas Stocking yet.
  15. I'm wondering from those of you using detectors much longer than I have what would you say was the first 'smart' detector? Part of this question will be a definition of smart. I think of smart as being a detector that can do more than just 'respond' to a signal. It would do some processing. Certainly smart devices now have chips with algorithms. Would you define smart as a detector with a coin meter? Just wondering. Many definitions of smart devices now say it is a connected device. I'm not very 'smart' so that is why I am asking the question. Mitchel
  16. I do what I can to foster competition that develops alternatives to the all too common VLF detector. There are plenty of options out there, but in my opinion they all weigh too much or cost too much. Usually both. I envision people out there with a popular VLF metal detector for beach, relic, or gold detecting. These machines all sell for around $700 and weigh 2.5 - 3.9 lbs. Perhaps they would like to add a ground balancing PI (GBPI) to what they have. I think that for "normal people" with normal budgets a machine under $2K and under four pounds just makes sense. It would be more than twice what they spent for their VLF, and in this day and age there is no reason why a decent PI should weigh over 4 lbs. I am drawing the hard line at 5 lbs and refuse to ever buy a metal detector again that weighs 5 lbs or over. I am setting under 4 lbs more as an aspirational goal that I think can be achieved, but recognize that battery power and coils are key inhibiting factors in high power PI systems that may make sacrifices in depth necessary to get total weight under 4 lbs. To clarify what I am talking about here, I should say that for many people a $700 VLF detector is a great place to start and in many cases is all a person ever needs. However, there are places where extreme ground mineralization and mineralized rocks (hot rocks) severely impede the performance and use of VLF detectors. Alternative technology to deal with these conditions has been developed, by far the most familiar being the Minelab ground balancing PI (GBPI) detectors. These differ from common PI detectors by having the ability to ground balance. Other brands have offered the Garrett Infinium (discontinued) plus Garrett ATX and the White's TDI models. These detectors are used not just for gold prospecting but also by relic hunters, beach detectorists, and others who face challenges regarding ground mineralization and VLF detectors. Frankly, in my opinion GBPI technology is largely maxed out. The main room for improvement comes now in better ergonomics at lower prices. This challenge therefore limits detectors to those that weigh under 4 pounds with battery included, and which sell brand new with warranty after discounts for under US$2000. Detectors need not be ground balancing PI models, but must offer similar ability to ignore mineralized ground and hot rocks that trouble VLF detectors. I am going to rate detectors as to their relative performance using what I call the "Minelab Rating Scale. Details here. 1. Minelab SD 2000 - crude first version, very poor on small gold, excellent on large deep gold 2. Minelab SD 2100 - vastly refined version of SD 2000 3. Minelab SD 2200 (all versions) - adds crude iron disc, ground tracking 4. Minelab GP Extreme - adds greatly improved sensitivity to small gold, overall performance boost. 5. Minelab GP 3000 - Refined GP Extreme 6. Minelab GP 3500 - Greatly refined GP 3000, last and best of analog models 7. Minelab GPX 4000 - First digital interface, rock solid threshold 8. Minelab GPX 4500 - Refined GPX 4000, solid performer 9. Minelab GPX 4800 - Released at same time as GPX 5000 as watered down version 10. Minelab GPX 5000 - Culmination of the series, current pinnacle of GBPI prospecting machine technology. All Minelab models leverage an existing base of over 100 coil options from tiny to huge. I am a very practical person when it comes to detecting. I know all the existing models and options by all brands very well, perhaps better than almost anyone. This is the way I look at it is this. If I personally were to spend a lot of money to go gold prospecting for one month, and needed a GBPI detector, considering machines past and present, what would I get and in what order of choice? Put aside concerns of age, warranty, etc. just assume functioning detectors. Here is the issue in a nutshell. On the Minelab scale of one to ten as listed above, I would be generous in rating the White's TDI SL as a 2. Same with the Garrett Infinium which I will mention in passing as it is no longer being made. If I was going to spend a month of my time and a lot of money going on a prospecting trip, I would choose a TDI in any version over the SD 2000. I might go with a TDI Pro over a SD 2100 but I would have to think real hard about that, and when push comes to shove I would go SD 2100 were it not for the realities of age I said to ignore. A newer TDI Pro might be a better bet than a very old SD 2100 from a reliability standpoint, but again, this would be a tough choice. The TDI SL not really. In my opinion I would be shooting myself in the foot to go on this hypothetical trip with a TDI SL instead of a SD 2100. You see the problem now? The Garrett ATX fares better. I would rate it a 3, roughly analogous to the SD 2200 variants. Still an agonizing choice really and the ATX being new versus SD 2200 being old might again be the tipping point, but from a pure prospecting options perspective the case can be made that the SD 2200 might be the better way to go. The problem for this challenge is the ATX weighs way over 4 lbs and sells for slightly over $2000. The price is close enough really but the 7 lb weight is way off. That's it folks. That is reality. The best of the best that the competition can offer can only go solidly up against models Minelab has not made in years. I am not saying that to be mean or as some kind of Minelab toadie, that is my pure unvarnished opinion as a guy who is pretty well versed on the subject. Let's bring it all home. This person with the $700 machine really, really wants that under 4 lb, under $2K GBPI machine, but if they do their homework they discover that truthfully, they would be better off shopping for a used Minelab than what the competition offers new. With the TDI SL rated as a 2 the ATX in a much lighter box at under $2K is a solid win as a 3. A well designed ATX with standard dry land coils would look very enticing as compared to the GP series Minelabs. But Garrett refuses to budge! White's can certainly do something, anything to improve the TDI SL. A battery that lasts all day would be a good start. In the end they are limited by the basic single channel design of the machine. The SD 2000 dual channel design was literally the answer to and the improvement on the single channel technology used in the TDI, the basics of which predate the SD 2000. Still, White's currently owns the under 4 lb under $2K GBPI category so they have the first out of the starting gate advantage. Anything they do would at the very least just show they have not given up. The Minelab MPS patent that formed the basis of the SD series has expired. Not sure about DVT, which formed the basis of the GP series. Where is the competition? What the heck is going on here? Much gnashing of teeth and pulling of hair is going on here, that's what!!! That is my challenge to the manufacturers. Under 4 lbs, under $2K, on the 1-10 scale I am offering, what is the best you can do? The TDI SL as a 2? Really? Yes, really, that is currently the best of the best in the brand new ground balancing PI, full warranty, under 4 lb, under $2k category. You can pick up a 3.5 lb TDI SL right now brand new for $1049. The White's TDI SL takes the crown. Note that a challenger has a half pound of weight they can add to the TDI SL and still make the 4 lb mark, and retail can be almost double the $1049 of the TDI SL and still come in at the 2K mark. I therefore do not think my challenge is outright crazy. Hopefully we will see more competition in this wide open category soon. I have been beating this drum for years to no avail, but I do have reason to believe we are finally going to see more alternatives soon. I hope. Maybe? All I know is I have had it. I sold both my 6.9 lb Garrett ATX and 7.2 lb Minelab GPZ 7000 and am boycotting metal detectors that weigh over 5 lbs from here on out. I don’t care how well they work, I simply refuse to buy such heavy beasts anymore. In the future I will support and give my dollars to companies that pay attention to and prioritize lightweight, more ergonomic designs. White's Electronics TSI SL metal detector
  17. I mostly hunt in lakes and the bottoms are mostly all sand. A test on a sandy beach with the Equinox 800 and Xp Orx, both hit hard on a 14k 3.7 gram gold ring buried at 14". For mild ground I don't see a need for multi frequency. I do like the multiple frequencies on the Orx. Is there an advantage to multi frequency in mild ground?
  18. THIS !! All the people boo hooing will be in line to get one at that price point. It will also force the hand of ML with their price structure. ML raised their price on the 800 and NM absolutely crushed that price point. The Legend doesn't have to be better, just equal to turn the fortunes in their favor. ML and their arrogant "obsolete" charge is foolish. Obsolete by definition means no longer produced or used. Many detectorist and their single frequency machines are still out there making great finds and having fun. Furthermore, single frequency detectors are still being made and sold. NM build quality is far and away superior to the Nox detectors.
  19. I thought I was pretty damn good, but this technology has me beat. https://www.nbcnews.com/science/environment/mining-gap-companies-push-find-raw-materials-electric-vehicle-boom-rcna5077 Might be time to invest?
  20. I often see posts on various forums where people use high GB phase numbers as examples of hot, mineralized ground. I thought that GB phase numbers are only indicative of the TYPE of ground(rock,soil,clay,salt). Rock, soil, and clay can actually be pretty benign or very mineralized. Isn't the determining factor for hot ground that affects metal detectors the amount of Fe3 in the soil? A phase reading of 89 may be mild soil if the amount of IRON in the soil is low. Conversely a phase reading of 65 may be very hot ground if the ground consists of clays with high iron content. Some VLF detectors now have Fe3 meters on them and the higher the reading is on that meter the more the ground will affect your detection depth and the accuracy of the VDI number(if supplied). It seems like many people are confused by this. I think it is important info that can affect your coil selection(size and type), the amount of discrimination you may choose to use, and the mode(all-metal or discriminate) that we run in. We need somebody that knows their stuff to give us a definitive answer!
  21. Metal detectors often seem to have a 'Depth Gauge'. How is it calculated? Is it the strength (or inverse of it) of the amplitude of the return signal? So, for instance, everything else being equal, the 'deep' target would mean either a stronger target at greater depth or a weaker shallow target?
  22. While we're all abuzz with the announcement and advertised feature and performance characteristics of the XP Deus II, I'm wondering about tests that distinguish between detectors' target separation abilities. 'Word on the street' is that in trashy iron sites, the original Deus is still the best available. Presumably those reports are based upon in-field testing, which of course is the real proof. But the downside is, (AFAIK) these are qualitative observations, not quantitative. Subjectivity involved? Unfortunately, yes. We do have Monte's Nail Board Test for a special case -- iron nails near a single coin, all in the same plane and typically all on the surface of the ground. Add depth combined with some mineralization (burying the MNB) and you've included another real world dimension. But in the field, multiple nearby targets are seldom in the same plane. So you hopefully see the purpose of this post. Has anyone seen/tried other methods to better simulate actual in-field conditions to differentiate between competing detectors to best be able to handle trashy sites?
  23. I love coinshooting, and I'm often in my local parks or private permissions searching for clad and silver coins. But I noticed that when digging up shallow clad coins (3 inches or less), my AT Max with the stock coil would say the coin is 6 inches down. Sometimes, a surface coin would read at being 4 inches deep. I didn't think this was that big of a deal, b/c I could always pull out my F-Pulse and see if the assumed coin target was truly shallow or not. Also, the incorrect depth reading wasn't keeping me from digging a desired target. Tonight, I read: and http://www.fisherlab.com/hobby/davejohnson/SearchcoilfieldshapeApril2012.pdf Both of these mentioned anomolies or issues with DD coils and shallow targets. Is what I'm experiencing with my shallow coins and AT Max one of these anomolies? Or is there something else going on?
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