first piece of followup testing, re: Minelab noise cancel...

While I have NOT done the complete testing of targets on my Explorer yet, and how the VDI changes with respect to noise cancel channel, I DID do a quick test on a silver Barber dime tonight.

Air testing outside, low EMI environment, roughly 4" from the coil, using an Explorer SE Pro at 26 manual sensitivity and SunRay X-5 coil...

At noise cancel channel 1, the dime was a very solid, never-varying 03-29 ID.
At noise cancel channel 5, the dime was a very solid, never-varying 03-29 ID.
At noise cancel channel 11, the dime averaged 05-28 ID, with an occasional 05-29.

I did a bit of depth testing; the average max air test distance on the dime was 9 1/2 inches, on ANY of the channels. There MAY have been 1/4" BETTER depth at noise channel 11, but basically no difference.

Steve

Interesting for sure and thats the way you learn....to further followup I would also test a medium gold ring in the mix....perhaps there is a happy medium somewhere in between
to become more efficient in both silver and gold or does one setting enhance silver and hurt you in the gold ring category or vice versa....personally I feel going the auto noise cancel route setsup your unit for max efficiency for the situation on hand in your neck of the woods but keep on experimenting as perhaps you are onto something...

Steve....... you may want to try a low conductor.... like a small 10Kt white gold ring............ time permitting.

I should note, I ran the depth test at higher sensitivity (30). At 26, depth was a good inch, if not a bit more, less...I didn't check it real close at 26, but got a substantial gain at 30. More to come...

Steve

That amazes me that even silver is changing that much in VDI. WOW! Why Minelab didn't have the forsite to adjust the VDI numbers via software based on the channels being used is BEYOND me. Seems like a simple five minute software hack. You know, there are many FBS guys who refuse to noise cancel once they start popping silver real good. I've heard of guys leaving the machine on that channel for all future hunts from here on out after that. My friend rarely noise cancels his Etrac, and I see him hunting right around power lines without any major issues that you'd think noise cancel would be needed for. I think he's decided he likes the channel it's on now. I always noise cancelled my Explorers, but based on what I've read now with these changing VDIs and making learn/accept/reject useless, I don't think I'd ever change channels on a FBS machine once I found what one I liked. I think there has been discussion in the past on other forums about which channels on the Explorer guys seemed to prefer to hitting harder (or seeming to) on silver at depth and such. I'd ask around the net about what channel seemed to like and then set it and forget it.

Now...I'm confused...Weren't there certain models you couldn't manually select the noise channels on? Like the XS or something? It's been a while since I've had my last EII so I don't remember if you can manually select the channel on that? I think you could but I never played with that.

Either way, big reason to pick and stick to one channel is so you learn the VDI for nickles, tabs, and of course certain coins then, if what you're saying is that it's even changing silver somewhat. That alone is reason I'll stick to one channel when I add another EII to my line up.

critterhunter...I'm starting to feel exactly the same way as you, and starting to reach the exact same conclusion...with one caveat...

I might find my "favorite" noise cancel channel for silver, and LEAVE it there, BUT -- might then see if there's one I like better for LOW conductors, and use THAT one when I hunt gold/nickels. Bottom line, we would be using "noise cancel channels" in a TOTALLY different way than what the manual tells you to; the drawback of doing it this way would be that I'm SURE there'd be times when "silent EMI" would hurt your depth on a given day, at a given site, and you wouldn't know it...

I'll add one more piece...I've found that on one or two channels, my Pro-Pointer, when turned on, will interfere greatly with my machine; on others, I hear NOTHING. SO, when picking my "favorite" channel, I'll likely include this variable in the puzzle...

This is very interesting stuff, IMO...and all these discussions (about the gold rings, and noise cancel, and VDI), and the testing that is being done as a result, have been very educational for me, personally...

Steve

I admire your perseverance Steve ought to cover it...this hobby is an never ending learning experience...and thanks for sharing...

I guess that why we have detectorists and fellows who swing detectors...

Why, thanks Dan! That perseverance I have, drives some people NUTS!

You are right, there are never-ending opportunities to learn new things in this hobby. And you are exactly right...there are folks who swing detectors, and there are detectorists. That's what's so terrific and unique about this forum...there seem to be an overwhelming number of the latter, here...which provides incredible opportunity for growth, for all who frequent this forum.

Steve

No critter, the XS has the noise cancel button on control box but it doesn't have to be used.
And it can be changed manually in menu.
When I first got my XS I noticed if I noise canceled multiple times in the same place, it would sometimes
land on different numbers....so that along with the fact that what steveg found out that it can move items on
conduct scale, I left mine at 5 from then on unless I was at a location and absolutely had to change for interference.
Still this isn't a big deal but it is nice to know... I wrote about it years ago....I don't know if I could find the post.
The difference is slight best to my recollection but it could affect tight patterns.
I never used patterns after learning the tones.....

Steve(MS) --

I have, like you said) also found that if I noise cancel multiple times, in succession, it will sometimes land on different numbers...which -- like you -- makes me feel like leaving it at one single number most of the time will not, usually, cause big issues. I too agree with you in that I tend to feel like a number around 5 or so is working well for me, also -- channel 5 is NOT one that has issues with my Pro-Pointer, and is one that seems not to be "extreme," in terms of VDI issues.

I will say though, that while the difference in ID values w.r.t. noise cancel channel being used IS slight, as you said, on SOME targets, it varies quite a bit more with some other types of targets. I need to do the complete testing to get a more precise handle on this, but the degree of ID variability seems to be related to two things -- one, it varies less on high conductors than on mid/low conductors, and two, it varies less on coins (high OR low conductor coins) than it does on rings, and other types of targets. In other words, ID is MOST consistent, in my testing so far, on a high-conductive coin. It is SECOND most consistent on a LOW-conductive coin, and is LEAST consistent on the other types of mid- to low-conductive targets I've tested, be they gold rings, or rectangular tabs, or whatever. Like I mentioned in another post, my personal gold wedding band is a solid 08-13 or 09-13 on noise cancel channel 11, it is about 08-19 through the middle channels, and is 08-21 to 08-22 on noise cancel channel 1! That is a HUGE range of IDs...and what was also surprising was, I also tested a rectangular tab that ID'd exactly the same as my ring, and it varied identically in its ID value as did my gold ring, as I changed noise cancel channel.

So, in summary, while the conductive number varied from 13 to 22 on my gold ring, as I changed from channel 11 to channel 1, a nickel varies only between 05 and 07, and a silver dime is roughly 28.5 to 29, between channel 11 and channel 1. And yes, while I don't use patterns either, and certainly hunt by sounds/tones vs. relying on ID numbers, I do look frequently at ID numbers as a "piece of information." While the ID -- once you learn how it behaves w.r.t. depth, is a fairly valuable piece of info when COIN hunting with an Explorer, I am learning that it is even MORE useless than I thought when hunting jewelry, as NOT ONLY can jewelry fall ANYWHERE on the spectrum, but WHERE it falls can also change DRASTICALLY depending upon noise cancel channel. Again, maybe not earth-shaking, but certainly educational...

Steve

I always have hoped that ML would use the stereo to allow conduct sounds say in left channel and ferrous sounds in right channel.
Though not particularly related to this thread, I always felt I might be able to tell alum from gold if that could be done.
Ferrous sounds as you probably already know is much more volatile that conduct sounds.
Through listening to both "tunes" at the same time, it may be possible to pickup on subtle differences.
But since I couldn't hear both at the same time, my theory can't be proven or disproved.

Interesting thought, Steve...I'm trying to imagine if I could get my mind to "process" two totally different sounds, one in each ear, but if I could, there could be some value to what you are suggesting...

Steve

Ever try hunting with the audio only in one ear? I had to stuff some foam in one of the muffs on my headphones because for some reason I only seemed to be hearing targets out of one ear and it drove me crazy. Not sure if it's my hearing or these latest headphones, because I never noticed before that I hear better or not out of one ear. Anyway, with the foam in one muff now the volume is equal out of both and I'm much more sane now...Well, at least a little more. :')

Steveg,

95% of my digging decisions are made by audio, 5% by VDI. Call me old fashion but if it doesn't sound right, it usually isn't. VDI is good for poor hearing and training but when the rubber meets the road, it's the audio that digs the goodies. IMHO.

Cuniagau

“Never approach a bull from the front, a horse from the rear or a fool from any direction.”

cuniagau -- point very well taken, and I agree. As obsessed as I am with "numbers" (that's the way my brain is wired!) I do make most dig decisions based on audio. I ALWAYS look at the VDI, and try to "figure out" what I think I'm about to dig, before I dig it -- I always "call my targets" in my mind, and the VDI helps me to do that. BUT, the "dig decision" has been made by how the AUDIO behaves, not the numbers. I dig many, many targets that don't "ID properly" -- but do so based on the audio characteristics. On OCCASION I go the other way -- dig a target that doesn't sound "right," but there's something in the numbers that I can't pass up. And, of COURSE, those are INVARIABLY non-keeper targets just about all the time...

Steve