The Unrealized Promise Of Multifrequency

[Steve Herschbach]

To be clear here I am talking genuine multifrequency. Not selectable frequency misleadingly labeled as multifrequency, so we are now supposed to say “simultaneous multifrequency” or SMF, to differentiate. Sorry, I’m calling BS on all that. Selectable frequency machines are still running in a single frequency. Just because you can pick the frequency is not new. Been around for decades! When I say multifrequency detector I mean multifrequency detector, a detector comparing two or more frequencies to get a desired result. I don’t need to change my thinking. Marketers need to stop calling selectable frequency machines multifrequency. It’s misleading, I’m not playing along any more, and handing out thumbs down to those that continue to do it. Machines are either single frequency or multifrequency. If you want to your your single frequency detector as being able to select frequencies, fine. But quit calling it multifrequency. Even Minelab never stooped that low, and they had single frequency detectors that allowed you to select frequencies, far before most did.

So what was the promise? Or more accurately, the hype, of multifrequency? It has been that multifrequency detects all targets, large or small, high conductor or low, all at the same time. As opposed to single frequency, where each frequency is strong in one way, but weak in another. To this day I see this said in marketing, and I constantly see users repeating it as some kind of fact.

More BS. As anyone who follows this should know by now, the underlying frequency mix still rules. Minelab calls it “weightings,” where each mix is weighted higher or lower frequency, depending on the desired end result. So we have high frequency weighting for gold prospectors, and low frequency weighting for saltwater, as the most obvious divide.

Multifrequency does have an inherent strength over single frequency. Comparing at least two diverse frequencies gives more ground and target information to the system. This, in particular, generally results in better target id capability. There also is a very real ground handling advantage on mineralized saltwater beaches.

But you can’t make multifrequency detector that runs in all frequencies at once, that will do the best on everything everywhere. If so we would not have all these different modes, Park, Field, Beach, and Gold. The end result is not much different than a selectable frequency detector. You have high frequency mixes, or medium, or low. Each serves a purpose. I still have to choose frequency modes, and it hardly matters if I am saying high single frequency for nuggets, or high frequency weighted mix for nuggets. If people were not told different, they would not actually know it is any different, except for the extra target id and ground handling capability.

So stop with the “multifrequency finds all targets across the entire range” nonsense. There is no multifrequency detector made that runs in one mode, and hits tiny gold nuggets, while also working perfectly well at the beach. That’s what we are being sold, and it’s simply not true. This is from an old post of mine about Equinox, and it’s what we really have:

Hottest (more sensitive to small targets, hot ground/rocks, and saltwater)

1. Gold Mode
2. Park Mode 2 and Field Mode 2
3. Park Mode 1 and Field Mode 1
4. Beach Mode 1
5. Beach Mode 2

Least Hot (less sensitive to small targets, hot ground/rocks, and saltwater)

Now seriously, just how different is that from a range of selectable single frequency, high to low?

What I’d to see is all this incorporated into a simple variable control. Instead of discrete modes and complicated explanations, give me a single control. Setting higher sets for progressively higher frequency mixes, setting lower goes to lower mixes. You simply set the control as high as your ground allows, which is basically they way we pick between the modes above anyway. Simplistically using my little chart above the control would have 5 - 7 levels.

I think attaching names to the modes misleads people anyway. There is no reason not to use Gold Mode to Relic hunt, or Beach Mode to hunt silver coins, but people get locked into thinking those mode names mean way more than they do, and I think some peoples detecting suffers as a result. Get rid of the names, and it frees your mind to a more open approach as to which modes work best under and given circumstance.

[delnorter]

Thank you Steve.

Mike

[CPT_GhostLight]

That certainly puts things into perspective. People get caught up in the hype too much and disregard the reality.

[burlguy]

7 minutes ago, Steve Herschbach said:

To be clear here I am talking genuine multifrequency. Not selectable frequency misleadingly labeled as multifrequency, so we are now supposed to say “simultaneous multifrequency” or SMF, to differentiate. Sorry, I’m calling BS on all that. Selectable frequency machines are still running in a single frequency. Just because you can pick the frequency is not new. Been around for decades! When I say multifrequency detector I mean multifrequency detector, a detector comparing two or more frequencies to get a desired result. I don’t need to change my thinking. Marketers need to stop calling selectable frequency machines multifrequency. It’s misleading, I’m not playing along any more, and handing out thumbs down to those that continue to do it. Machines are either single frequency or multifrequency. If you want to your your single frequency detector as being able to select frequencies, fine. But quit calling it multifrequency. Even Minelab never stooped that low, and they had single frequency detectors that allowed you to select frequencies. far before most did.

So what was the promise? Or more accurately, the hype, of multifrequency? It has been that multifrequency detects all targets, large or small, high conductor or low, all at the same time. As opposed to single frequency, where each frequency is strong in one way, but weak in another. To this day I see this said in marketing, and I constantly see users repeating it as some kind of fact.

More BS. As anyone who follows this should know by now, the underlying frequency mix still rules. Minelab calls it “weightings,” where each mix is weighted higher or lower frequency, depending on the desired end result. So we have high frequency weighting for gold prospectors, and low frequency weighting for saltwater, as the most obvious divide.

Mumtifrequency does have an inherent strength over single frequency. Comparing at least two diverse frequencies gives more ground and target information to the system. This, in particular, generally results in better target id capability. There also is a very real ground handling advantage on mineralized saltwater beaches.

But you can’t make multifrequency detector that runs in all frequencies at once, that will do the best on everything everywhere. If so we would not have all these different modes, Park, Field, Beach, and Gold. The end result is not much different than a selectable frequency detector. You have high frequency mixes, or medium, or low. Each serves a purpose. I still have to choose frequency modes, and it hardly matters if I am saying high single frequency for nuggets, or high frequency weighted mix for nuggets. If people were not told different, they would not actually know it is any different, except for the extra target id and ground handling capability.

So stop with the “multifrequency finds all targets across the entire range” nonsense. It’s simply not true. There is no multifrequency detector made that runs in one mode, and hits tiny gold nuggets, while also working perfectly well at the beach. That’s what we are being sold, and it’s simply not true.

 Thats why the v3i was so revolutionary. Using 3 frequencies... you can see the target strength in all 3 frequencies at once using Stereo Mixed mode during real time search, not just pinpoint.

 By selecting either, "best data",  it would alert you of a target in your selected vdi range hitting on one of the 3 frequencies.
 If "correlate" was selected you could set the amount of "span" or difference of target response for the 3 separate frequencies so that it would not identify the target unless it fell into the selected VDI range for all 3 frequencies. 

[maxxkatt]

That has confused a lot of new Nox 800 users. I think that is why the advice to newbies (and most others) using the 800 is to pick their mode and don't try to roll your own unless you really, really know what you are doing. Speaking from 3 years experience with the 800, I tried to roll my own with advanced features way before I knew what I was doing. Thus looking back, I was often hunting with a badly tuned 800 that really degraded my ability to find any good targets. Sad, but true for me. I now use a CTX3030 that makes it much easier for the user to select a few options that are crystal clear, like ferrous ground or ferrous coin or high trash, low trash. These modes are even described accurately.

 

[Steve Herschbach]

I would further comment that in general, when talking single frequency, you have only three useful ranges. High frequency for low conductive small targets. Low frequency for high conductor large targets, and salt conditions. And mid frequency as best all around.

The exact same thing is true in multifrequency.  High frequency mix for low conductive small targets. Low frequency mix for high conductor large targets, and salt conditions. And mid frequency mix as best all around.

If you look hard at Equinox modes, frequency differences is only half the story. Some modes are the same frequency mix, and all that differs is preset in target id notching, recovery speed, and even transmit power. There are not as many frequency mixes are there are modes. It still boils down to high, medium, and low.

[nickelNdimed]

22 minutes ago, Steve Herschbach said:

I would further comment that in general, when talking single frequency, you have only three useful ranges. High frequency for low conductive small targets. Low frequency for high conductor large targets, and salt conditions. And mid frequency as best all around.

The exact same thing is true in multifrequency.  High frequency mix for low conductive small targets. Low frequency mix for high conductor large targets, and salt conditions. And mid frequency mix as best all around.

If you look hard at Equinox modes, frequency differences is only half the story. Some modes are the same frequency mix, and all that differs is preset in target id notching, recovery speed, and even transmit power. There are not as many frequency mixes are there are modes. It still boils down to high, medium, and low.

Even more true for 600 model where the gold modes don’t exist. And if not at salt water location, really it is down to two options and 2 modes each more preferences in user settings.  One modes and Two modes. Yes a park may have different levels or kinds of trash but is a park not really just a field with benches and playgrounds on it once you  work through the modern trash? That’s the way I have been thinking about it. 

[GB_Amateur]

It seems that recently there's been a marketing ploy to make a (complicated) new detector attractive to a broad audience:  give the advanced detectorist lots of (virtual) knobs and switches to configure the detector exactly the way s/he wants it while at the same time giving the less advanced detectorist, or an advanced detectorist who likes a simple detector with minimum need for adjustment, to simultaneously (oops, there's that word again 😁) be happy with the same detector.

I was confused by the differences between the five modes (or is it 10 modes -- see I'm still confused) on the Minelab Equinox 800.

Did all the negative response to the White's Vision family result in a significant impact of all future MF detectors?  I never really understood the public's dislike of that detector's settings options, but then I'm a "give me everything, including the kitchen sink and let me decide" kind of user.  I don't use many of the Equinox's settings or even modes, but I'm not complaining that they are there.  They aren't poisonous creatures just waiting for the right time to bite me.  (I do wish they had explained things better, such as only difference between Gold 1 and Gold 2 being the default settings.)  Meanwhile I absolutely live by being able to set all the tone options in five tone mode that the 800 model (but not 600 model) allows.  Canned settings have their place as a baseline and starting point (and 'returning' point if one gets things too far out-of-whack) but don't dumb it down so much that we have to get the real scoop from a third party forum (because some members actually have inside knowledge from having helped in the development and/or initial testing) as opposed to being able to get that info from an OEM user manual.

(See what you've started, Steve.  )

[JCR]

I'm to the point now where I can choose a frequency with good confidence in how it will relate to site conditions & intended targets. What I wish I had more insight into is how the different "modes" are set up as far as filtering & signal processing. What is the difference between Park & Field? What is different in Beach? Then I can I can experiment instead of just blindly guess. The typical User's Manual is very vague. XP seems to give a little more info.

[☠ Cipher]

1 hour ago, GB_Amateur said:

Did all the negative response to the White's Vision family result in a significant impact of all future MF detectors?  I never really understood the public's dislike of that detector's settings options

When it comes to the V series, they tend to be fine in mild ground. With the right coil, even great. But as conditions worsen, moderate to harsh, or rapidly changing, they just don’t perform as well as other multifrequency designs. One of the Engineers, Geotech, explains that it’s the result of poor filtering of the frequencies, leading to frequency crosstalk, making a good ground balance especially difficult. If it were a better performer in such conditions I believe the complexity would’ve been forgiven. I have one and I love it, but I also have 0-2 bar soil, and rarely have opportunity to get to a saltwater beach. As they are, complex with compromised performance in difficult ground, the V series lends to too much chasing one’s tail for many people. For them, more time is spent looking for the holy grail setup than detecting.