GPX 6000 Noise

[hAyyoUinAU]

Gday guys, just seeing what peoples thoughts are on the 6000 and excess noise. Coming from GPZ 7000 and SDC 23000 to a GPX has been a little strange for me.
It likes to ping GHOST signals, especially when the ground is wet. Clay is OMG, especially if it is red. Even just 1 inch of the clay it goes off, I was even so positive I had a target I even panned the clay to check. Nothing.
Swung a GM over the same clay and it was dead silent. I had the 11" Sensitivity all the way down and still screamed. Tried to balance out the clay, forget about it.
I had this unit turn of on me by itself the first time I took it out when I put it on the ground (not dropped but bumped). I took of the speaker cover and reconnected the plug they say sometimes can be a little loose.
Today was my second time out with the 6 and now I am really questioning whether I got one of the dodgy faulty ones floating around. I know there has been some trouble with some units.
And after my 7000 unit just cold dying on me without any reason in the past, I am really trying to figure this out.

I don't think an 8000 dollar machine should false on a target that the SDC doesn't.

Anyways, I have read a couple posts about some issues, but just wondering if anyone else has had similar experiences.

I understand having to use the 14" for EMI and Salty ground etc etc, but like I said, GM can handle the same clay, and so could the SDC. Confused.

 

[grubstake]

Sounds a bit suss to me, Rick. Is there anybody local with a 6000 who you could get together with to compare machine responses?

 

[mbasko]

The GPX6000 can certainly be affected by wet, mineralised ground but not to the point of being unusable?
I've had some trouble with wet, red clay over the past few weeks & have persevered with the 11" mono when I should have really tried the 14DD.
It's not a huge surprise to me as I've experienced similar with mono coils, especially newer flat/spiral wound, with GPX4500/5000's when the smarter thing to do would be change coil to a traditional bundle wound mono or DD.
In my experience the SDC & GPZ both handle this type of ground better but not without some issues.
It to me seems like more of a MPS Pulse Induction issue (the SDC being MPF seems to handle it better). Coupled with the pretty insane sensitivity of the 6000 this wet, red ground looks like it will be an ongoing issue - hopefully some smaller DD's come out for it?
I was hoping to try the 14DD on a troublesome area this week, as I've been told it works great & maintains a lot of sensitivity, but that's looking unlikely - maybe next week.

 

[hAyyoUinAU]

I am going to put the 14DD on and return the 11" to get it tested. In the meantime I can see how the 14 runs. Sux because the 11 is such a sweet size

I will let you guys know after the weekend how it goes

 

[hAyyoUinAU]

Sounds a bit suss to me, Rick. Is there anybody local with a 6000 who you could get together with to compare machine responses?

I will drop the 11 with Justin at Lost Treasures where I bought it from.

 

[Dean Mortimer]

Your coil might need replacing. Minelab has a fault with all GPX 6000 coils. there is no padding inside the coil so every time you swing the coil the wiring gets knocked around inside and slowly tears off the very thin aluminium shielding to the point the coil becomes excessively noisy. I have been through a few coils myself. Wet ground it also doesn't like. Dry red clay is not an issue, if you get a lot of noise when red clay is dry get your coil tested as its probably defective which over happens in time to all GPX6000 coils.

Also I have found the GPX6000 will track out targets very quickly regardless of settings used. Only way to bring them back is by ground balancing, but a few sweeps over the target again and there gone again.

 

[mbasko]

Your coil might need replacing. Minelab has a fault with all GPX 6000 coils. there is no padding inside the coil so every time you swing the coil the wiring gets knocked around inside and slowly tears off the very thin aluminium shielding to the point the coil becomes excessively noisy. I have been through a few coils myself. Wet ground it also doesn't like. Dry red clay is not an issue, if you get a lot of noise when red clay is dry get your coil tested as its probably defective which over happens in time to all GPX6000 coils.

Also I have found the GPX6000 will track out targets very quickly regardless of settings used. Only way to bring them back is by ground balancing, but a few sweeps over the target again and there gone again.

Not good about the coils & have heard of a few failing but not had it happen to mine yet - touch wood.
My 6000 was a first release & the 11" mono is pretty much the only coil I've used on it (apart from about ~6hrs with the 17"). My mates machine is the same age & he's never had the 11" off it & it's still ok to.
In saying that we both had control box issues that needed return to Minelab for warranty repair so not all rosey for us either.
I think there's been some serious quality control issues with this model & hopefully Minelab have addressed that as it's less than adequate for an expensive detector.
Since my initial problem was repaired & all gear checked by Minelab I can't fault mine though. Very impressed with it overall.

 

[hAyyoUinAU]

What confuses me is , how can the 6000 not like wet ground, yet the coils are water proof. My SDC loves rain, water, mud, clay, you name it, it can handle it. I was under the impression that the 6000 was similar to an SDC but with a few more adjustable options and more sensitive. (On gold)
I hope my unit is not faulty. Then again, now I do, because when I have seen and heard the machine running well, it seems amazing and the ideal upgrade to the SDC.

 

[mbasko]

It's not new & some have even complained of noise in wet ground with the SDC & GPZ7000.
Also it's not predominantly the moisture or water in the ground that causes the issue but how the ground signal reacts/changes when the ground (or ground minerals) is wet.
Here's some old threads going back several years & prior to the 6000:
https://www.prospectingaustralia.com/threads/noisy-ground-after-rain.12917/#post-172162
https://www.prospectingaustralia.com/threads/gpx4500-coil-choice-for-wet-ground.39305/
https://www.prospectingaustralia.com/threads/gpz7000-ground-noise-in-the-wet.34303/
https://www.prospectingaustralia.com/threads/just-how-noisy-can-ground-noise-get.34519/#post-559740
I think this paragraph from Nenad says a lot too:

Ground is a funny thing. If the ground is positively mineralised, i.e. lots of iron, or thick red clay, then a larger (less sensitive) coil will run quieter. But if the ground has any salt in it, moisture will enhance its conductive nature, and in this case a smaller coil will actually run quieter. This is very evident when you try to run PI gold machines on the wet sand at the beach.

So in some areas the larger 17" mono may be worth trying, although it's still a very sensitive coil, & in others that contain any salt then the 14"DD.

Unfortunately it's just something else we have to contend with along with man-made EMI, natural atmospherics, variable ground & so on.
As seen it's not really unique to one machine & likely more dependent on area.
Putting out an extremely sensitive PI machine like the 6000 hasn't helped in these type of areas but IMO it's doable with some perseverance, using manual settings & if needed using the DD coil.

 

[Teemore]

What confuses me is , how can the 6000 not like wet ground, yet the coils are water proof. My SDC loves rain, water, mud, clay, you name it, it can handle it. I was under the impression that the 6000 was similar to an SDC but with a few more adjustable options and more sensitive. (On gold)
I hope my unit is not faulty. Then again, now I do, because when I have seen and heard the machine running well, it seems amazing and the ideal upgrade to the SDC.

If it really is a faulty coil your dealer should be able to fix that for you.
As to reaction in wet clay soils, yes noticed this last winter, and creeping in again now .........
If it looks like wet clay when you scrape off an inch or so, ground balance on the waste pile and then try again where you thought the target was ... it it's wet ground the signal should disappear. Repeat at another inch or so if still iffy.

 

[hAyyoUinAU]

Okay, so I am still not convinced everything is all okay with my 6000. It reset once today when I dropped it again slightly on the ground.
However, I did manage to persist with the 11inch today out at Durikai. There was no EMI, which I do not have a problem with anyway, its just getting used to the machine and how it responds to the ground. A couple of signals I had disappear on me, and I run out of time to check properly.
In saying that, I did score a little 0.2 gram nuggie today and only a few bits of junk. Not T bag.
Apparently Smokey was there as well, but I kept to myself as I was trying to test this machine out and help my mate out with his new GM.
I will be doing more tests in next couple of days. Will keep people posted.
Cheers

 

[hAyyoUinAU]

Still having issues with the 6000.

1. Headphones have a constant noise in the background, I have good ears, I can hear it. Resetting bluetooth or unit made no difference.
2. Headphones start to make a high pitch faint squeal when near coil with scoop, which is annoying. SDC nor the GPZ did that.
3. Falsing/Ground noise (even dry ground) from any sort of mineralised soil. Soil that the SDC and GPZ could handle fine. Can not ground balance the noise out. Not EMI.
4. Once it has restarted by itself when dropped on ground and another time it switched off.

I am going out this weekend with someone who has a GPX 6000 with not issues to compare and test.
I will keep everyone posted.

I wonder if Minelab deciding to build and QC this machine entirely off shore was a good thing.
I just don't see the "ALL GOLD, ALL SOILS, ALL THE TIME" when in reality it should be "ALL GOLD, SOME SOILS, SOME TIMES"

PS.
I have factory reset plenty of times, I have started the unit and let it settle down for a while. I have noise cancelled until the cows come home.
I have lowered the sensitivity to the lowest setting possible. I go slow, giving it time, I have tried everything recommended. Manual tracking doesnt help at all.
Every now and then(not very often), the machine does run quiet, but not for long.

 

[mbasko]

I wonder if Minelab deciding to build and QC this machine entirely off shore was a good thing.

They have all been built offshore since the last Australian made GPX4500's (first release not second).
IMO your GPX6000 may have issues & may need to be looked at?
Have you given the 11" coil back to your dealer or discussed all of the issues you're experiencing with them?
That would be my first port of call.

 

[hAyyoUinAU]

They have all been built offshore since the last Australian made GPX4500's (first release not second).
IMO your GPX6000 may have issues & may need to be looked at?
Have you given the 11" coil back to your dealer or discussed all of the issues you're experiencing with them?
That would be my first port of call.

I was told today that this is the first Minelab machine to have EVERYTHING done off shore, including QC. Before QC was done local.
I have been in touch with my dealer, who has not had any other complaints besides me. Lucky me.
I am getting them to test it over the weekend. I will let you know what they say.
Im thinking I have a dud

 

[davent]

One of mates is a dealer also. He has sold a lot of 6000s. He has had some problems. To be fair, minelab have been great dealing with these, and sometimes, a quick exchange was done in store while the customer is there.
My 11" was replaced on the spot.
But there have been quite a few problems for a new machine, and an expensive machine at that.
That's my opinion anyway.
I have a zed and a 6k.
I am really trying to like the 6k.
Trying.....

 

[Jaros]

Maybe keep the Zed warmed up in the background.

 

[davent]

My advice to someone who is about to fork out $8000 for a metal detector would be, find another $1500 and buy 7000, or find a 2nd hand zed with few extras like spare battery or coils.

 

[Jaros]

I think they need some QC by someone in the country they are selling to- like Nenad.

 

[mbasko]

My advice to someone who is about to fork out $8000 for a metal detector would be, find another $1500 and buy 7000, or find a 2nd hand zed with few extras like spare battery or coils.

Horses for courses Dave.
Some can't swing the GPZ for long periods & want something lighter with a bit more boogey than a SDC gives.
The GPZ can be a cumbersome bit of kit in some eastern state areas too. Being trussed up in harnesses with guide arms etc. isn't my idea of fun on the side of a gold bearing hill.
For my areas the 6000 has been great, I wouldn't swap it for a GPZ here, even if it can be a bit cantankerous at times .
I liken it to driving a sports car. To get the best out of it you've gotta stay on the controls & know when to back off on the throttle.

 

[mbasko]

I think they need some QC by someone in the country they are selling to- like Nenad.

QC needs to be done by final design engineers & the manufacturers (Plexus Corp. if they are still running Minelabs manufacturing?)
Nenad may have had some input during the testing phase, not sure? Testers have said on a number of newer releases that while they give their honest opinion it's not always implemented at final design & manufacturing stage.
I don't see how a supplier like Nenad can control a multinational companies QC? I don't doubt he'd do it justice though.
Many of the issues, from what a technician told me, are 5min fixes for them so that in itself suggests the manufacturing QC is lacking.