Experience with Golden Mask GM5 Finder after half a year of use

I was looking forward to Golden Mask GM5. As the first reports and bits of information came in before the launch, the excitement grew more and more.Andwhen the GM5 Finder finally arrived for my test, I fell in love with it at first sight: the slim modern design and sexy look made an impression. But nothing is just about looks... Now I must
warn the readers of this review: I am writing it exactly as I recognized the detector from the first moment to the present. And it is not always true that the first impression is the most important, as you will soon see. I recommend skipping the next three paragraphs for the weaker characters.

First impressions

For the love of sobriety...

When I first set off excitedly into the field, there was a properly cold shower. I was already used to the GM4's clear tones, I knew how the detector behaved and, having been informed that the GM5 was actually a "GM4 with a display and a few extra features", I expected everything to go like clockwork straight away. It didn't. I was neither wise nor cheerful about it. I couldn't tune the ground satisfactorily, didn't know how discrimination (mis)manifests itself, was annoyed with the POWER LEVEL setting, and the detector somehow behaved all differently than I expected...

Thus I was forced to open the manual. There I read how to Ground Balance and other information, which of course didn't quite and always apply, as I learned over time and with increasing practice. It took me a while to figure out my own before I started operating the detector to my full satisfaction.

Of course, the second impression was not the best either. Discovering that the GM5 has a battery with a capacity of only 1,000 mAh, which became apparent on the second day shortly after the search began, did not add to the good mood. And then when I did my own in-depth tests and found out that the range is also not great and the GM5 doesn't beat the GM4 in range, and it loses slightly on small targets, I slowly fell into frustration...

Gradual convergence

There are two kinds of love: At first sight, the quick kind, it rarely lasts... And then the gradual one, where there is a gradual getting to know each other, the breaking down of prejudices, pretenses, and the relationship slowly matures. And that's exactly what happened to me with GM5... When I overcame the first partner disagreements in the sweat of my face, when I threw away the initial dissatisfaction and finally started to notice the advantages of the detector, that's when I started to understand the GM5. Gradually, I found the positives I had worked hard on and the apparent weaknesses of the "five" eventually ceased to matter. Eventually I got so comfortable with the GM5 that it is only with a heavy heart that I will now return it... So much for the introduction and below for the review itself.
Design, battery, wireless headphones

The detector is well handled, solidly balanced, as is GM's wont. The construction itself is very solid and rigid. The ability to adjust the desired length to the exact millimeter of the character is awesome. One is not limited by anything and can fine tune the design really precisely. For example, I build my design with the unit slightly "off axis" so that I can look at the display well and not have to rotate my arm while viewing the display. I'm practically deliberately doing what once bothered some people about the GM4 - I'm fine with it, though. Compared to the GM4, which has S-shaped bars, the GM5's straight telescopic design has to be a bit longer. It's just a matter of habit, it doesn't particularly affect the balance. I was a bit worried about the hard plastic handle, but there was no reason to be. The grip is solid, it doesn't slip, no calluses, so I'm happy with the construction and appearance.

As far as the battery capacity of the detector is concerned, it is now possible to get 1,500 mAh batteries on request, which guarantees some 12 hours of operation and that's not bad. Still, I would have preferred a battery life like the GM4, i.e. around 20 hours, which is ideal for weekend searches without charging. However, the battery pack can be slid out and the rechargeable cells replaced with others, similar to previous GM models.
The WS 105 wireless headphones don't switch off, they hold up, sound reproduction is good, and lag is virtually zero. These headphones are good and a joy to search with. Plus, they are nicely constructed, fit well on the head, and have flair. My only complaint: The lack of a headphone jack to connect my own. This option was available with the previous version of the WS 107 headphones. But it's nothing I would change these headphones for.

Ground Balance - ground effect detuning

Ground tuning is essential. It was supposed to be simplified in the GM5 compared to the GM4; the five now have automatic and manual detuning. I have to admit that I groped around quite a bit at first and spent some time tinkering before I settled on a procedure that I still follow today. In the GM5 manual you will read that pumping after the selected detuning mode (manual or automatic) should be slow, with one cycle of movement taking about 2 seconds. In real life, however, pumping much faster has worked for me. You need to try it; in some locations the detector seemed to not react to ground effect at all and I had to pump really briskly to fine tune. Where the ground effect was strong, on the other hand, much slower...

With some bitterness I have to say that GM5 has problems with tuning on basalts. This is to be expected, after all, this is a weakness of the vast majority of VLF detectors and I didn't believe that the GM5 was any different from the GM4. On the other hand, by changing the frequency and channel one can get a decent detuning result in certain circumstances, it just takes some trial and error. In heavily reddened locations it is better to go in mono mode. The 23 cm Spider worked best for me on basalts.

The procedure of debugging GB:

I always tune the GB in the manual. I find it more accurate, it feels better to search on it. After switching on the detector I select "GB", switch to "MANUAL", go down to zero and long press ENTER to reset the detector. Then, again in the GB menu, I select "MANUAL" and slowly increase the values while simultaneously pumping within the range of audible hum (the worse the conditions, the slower). The moment the detector goes quiet, it is detuned. Interestingly, at the various sites where I've used roughly the same GB settings with the GM4, it's quite different with the GM5. I can't tell if this is because the GM5 is more sensitive to ground effect and can be more accurately detuned. The values in manual GB mode tend to be in the 15 to 45 range under different conditions and with different probes, most often I have had them around 25.

Discrimination and its modes

The GM5 has three search modes, and the "all" and "2" modes are unaffected by the degree of discrimination selected. It only shows up in the "mono" mode, which I really liked. In this mode I mostly walk in areas heavily littered with tinfoil or small iron and I have to sayI have to say that even where I usually gave up with GM4, I can still pick up valuable targets with GM5 and Spider 23 probe. And I really enjoy it!
I use the "all" mode (i.e. All Metals with one tone) most often when I'm searching forwhen I literally clean every beep, in the woods and also when I want to verify a boundary signal. Most often when I "suspect" a coin deposited on a treble or a signal at the edge of range. This mode is also useful when searching with a deep barrel and in places where there is minimal waste.

I choose the two-tone mode mainly in fields and meadows where there is not so much waste. The GM5 can adjust the pitch for both ferrous and non-ferrous metals separately. This makes it easy to fine-tune the most appropriate combination of tones to suit your needs. I use the higher tones for the colors and the deepest (called "farting") for the scrap and small irons.

Discrimination in mono mode

At first, I was going in the recommended values, trying higher settings, but eventually I "settled" on one. At this value the detector is impeccably usable, confident and stable in target presentation. The sizzle and the muffled intermittent tones of small debris are clearly distinguishable from the paint and, especially in combination with the display, the signal evaluation is really easy. I only give a B where there is really extreme amounts of trash.
I can clearly see any (even large iron) on the display, I can almost always recognize foil, beer corks, etc. So the moment I hear a color in unison, I don't have to switch to two-tone to verify, I just glance at the display and I'm clear. That's the tremendous power of the "GeEmFive" and I think a lot of GM5 owners now know exactly what I'm talking about :-) And for those who haven't yet experienced the magic of unison in waste-infested locations, I definitely recommend this mode.

Change frequency and POWER LEVEL

The GM5 has two operating frequencies (8 and 18 kHz) and two operating channels to each. In fields, meadows, gardens, and small target dense areas, I most often go with the 18 kHz frequency on the first channel. However, there have been locations where I have not found my favorite "18" - usually some interference. Sometimes it helped to switch to the second 18 kHz channel with a simultaneous POWER LEVEL reduction, other times I had to set it to 8 kHz. By the way, I like to use this frequency in the woods and where I want to look for rather larger targets and I'm not so concerned about separation. Then I like to combine it with the "all" mode

In total there are 4 working modes available (always two channels for each frequency), so GM5 is more usable than GM4 as far as interference is concerned. I must admit, however, that I have known heavily jammed places where neither frequency nor the selected channel was picked up, however, my friend's Nokta Fors Core had problems in the same places. In such locations, sometimes changing probes (I always carry Spider 23 cm and Mars Discovery for different conditions) and lowering the sensitivity below 20 helped.
I have observed that in a quiet location, where there is minimal ground influence at the same time, I am able to operate at 18 kHz in the "I" channel without any problems (i.e., ringing and tresholde) quietly at steps 28 - 29. If I switch to channel "II" in such a place, I have to lower it below 25.
Generally, a stable 25 is recommended, but if the situation allows it, the site is clear and the detector is still quiet, increase the PL as far as it will go. I have experienced that, especially on small targets with the Spider 30 cm and Mars Discovery probes, the downward shift in POWER LEVEL is already quite noticeable. Least of all the Spider 23 cm, which seems to me to be absolutely ideal for small targets and doesn't lose any range compared to the GM4 with the GM5.

Ranges, separation and probes

I walked the detector with three probes: the Spider 23 and 30 cm, and later the Mars Discovery. I was somewhat disappointed with the Spider 30 cm in the field. GM5 does not go as deep with this probe as GM4. Still, it retained good separation capabilities and discrimination was not a problem either. However, my initial disappointment with the loss of range (although it was not significant, about 2-3 cm loss on a target the size of a bipodRU) compared to the GM4 led me to request the opportunity to test the Mars Discovery lander with the GM5, which, for example, makes incredible depths on the LP Zero.
Mara obliged me and sent me the probe in early spring. The detector moved up in range, but compared to GM4, which I also tested at the same time with Mars Discovery, it was still behind. The GM5's ranges were a bit above those of the GM4 with Spider 30 cm, but the GM4 with Mars Discovery still goes a bit deeper.
But the Spider 23 cm probe pleasantly surprised me. Not only does it not lose any range compared to the GM4 with five, but the separation capabilities are excellent, the search accuracy is excellent, and the signal presentation on the chart is almost perfectly accurate with this probe! Yes, of all the probes tested, the one I enjoyed the most on the GM5 was the smallest one tested and often underestimated, the Spider 23.

Summary: Once you understand the GM5, you will fall in love with it.

As time went on, I became more and more comfortable with the GM5. When I found out where its main strengths lay; i.e. separation, the ability to present accurately thanks to the display and thus its great use, among other things, on "walked" and bogged down sites, I started to enjoy the search again. If I were to define the ideal use of the GM5, it is clearly fields and meadows with a focus on small targets, coins and jewellery. Literally like a fish in water, the GM5 feels at home in trash infested environments, i.e. wherever there is a lot of small tinfoil, zinc and other such "goodies". It recognizes irons perfectly, even if they're big, holey, forged and hollow, you can just see it on that display.
It can handle some interference that the GM4 couldn't. Separately, it's on par or (at least perceptually) better than the GM4. Audio response speed is excellent, the graph is logically a bit slower in that regard. With the small 23 cm Spider probe, it is no match for the GM4 on range. However, thanks to the display and the graphical signal evaluation, the GM5's presentation abilities are close to 100% certainty once it is mounted. In this respect, the GM5 is hardly a match for anything in its price class.

When compared to the GM4, the GM5 is a much more adaptable machine with more setup options, which for me personally completely trumps the fact that the GM4 easily leads on range. The VDI chart is such a powerful aid and tool for accurate and efficient searching that I'll gladly skip the few inches of range... I was pleased to be able to change the pitches of the colour signals and iron separately, which is an absolutely great thing in mode 2. Also, the backlighting of the display (a bit unusually by double pressing POWER LEVEL) and the LCD contrast adjustment (by arrow keys without entering the menu) are welcomed with appreciation.

If you want to enjoy the search and don't want to dig every piece of tinfoil, i.e. "scout" valuable targets even in locations where others run away helplessly, the GM5 is the ideal choice. I'd recommend the 23 cm Spider probe variant and adding the Mars Discovery. You will get an accurate, fast and reliable detector for crumbling in fields and meadows, with "Mars" then into the woods for depth.

Positives:
- Honest construction, durability, appearance
- Great separation, recovery speed
- Accurate graphic presentation of the signal
- 3 search modes, very good discrimination
- 2 frequencies + 2 channels for quieter searching in different conditions
- Graphical representation of the signal is unrivalled in this price range at this quality
- Detector handles better external interference than previous GM versions
- Backlit display (on/off options, contrast)
- Cleverly and logically sizedwall-mounted control buttons
- Possibility to adjust the heightTone settings for both ferrous and non-ferrous metals separately
-Hassle-free wireless headphones
Negatives
- Slightly weaker range compared to GM4
- Worse battery 8 hours battery life with 1,000 mAh, 12 hours with 1,500 mAh
- Graphical signal rendering could be faster
- Debugging issuesm on basalts

As a follow-up to the review, there will be a video from the field with specific examples of real targets before excavation and their representation on the display using the VDI graph and analysis. A separate chapter will be a review of the Mars Discovery lander, which even "zeros" and "fours" can look forward to :-)