XP Deus 2 Conductive Soil Subtraction

[maxxkatt]

I have been studying the effects of some of the factory program settings.

Programs #1, #9 (General, Relic) use a secret sauce called conductive soil subtraction. The best I can tell for researching this is that it is supposed to counter some negative effects of wet soil. Ion halo effect and iron falsing. I didn't know moist soil affected iron falsing. Maybe the ion halo effect does something to a piece of iron and makes it false?

Specifically the ion halo effect that makes metal items seem larger to the detector than they really are. My understanding is that metal ions flow out from metallic objects into the surrounding soil and can make the small metal object appear larger to the metal detector. How long does it take for metallic ions for flow out into the moist soil? after 1 day, 3 months, or 6 years?

The question is then do I just use PGMS #1 General and #9 relic for wet soil? Is there really any difference if you set up pgm #1 general and say pgm #4 Fast pretty much the same way in moist soil? Will you find more good targets in wet soil using PGM #1 General than PGM #4 Fast? Is this wet/non-wet soil selection even worth fooling with?

And then there is frequency addition used in some of the other factory programs. I have no idea what this does in terms of being better or worse for different situations and why it is used in some factory programs and not others. 

If you have any knowledge or actual experience with this topic, please share with me on this thread. I may be worrying about this and it is not an item to be worried about.

 

 

 

[JCR]

 I'm surprised no one has replied to this even though it is a subject that is somewhat getting into the "weeds" on detector operation.

 The D2 manual shows program #1 General to have Conductive Soil Subtraction, along with programs #10 Diving, #11 Beach & #12 Beach Sensitive.   Relic is program #9 and the manual states it has Frequency Subtraction. Nothing about conductive soil.

General & Relic are totally different types of programs. General being a motion based Disc/Tone ID mode same as #2,3,4,5&6.   Relic is a Motion based All Metal mode like #8 Gold Field.

As far as Conductive Soil Subtraction, that is a signal processing method that removes the response/sensitivity of conductive ground. Some low lying inland sites, when water logged will give false ground signals around the foil range TID, or even heavy mineralized sites with a lot of small iron bits scattered in the soil(think fuzzy magnet) when well wet. By using Conductive Soil Subtraction the detector better ignores these ghost signals & allows you to run near normal Sensitivity levels.   I suspect that Relic's Frequency Subtraction deals with the Ground response as opposed to conductivity.

 Frequency Addition is also a signal processing method. This is a little less clear to me but the detector is utilizing more than the one primary frequency to determine target ID.

 In the end, the magic secret sauce of modern SMF detectors is in how the signals are processed.

[Jeff McClendon]

Thanks for replying JCR. 

I didn't want to reply since I have not used the General or Beach programs much at all yet.

Relic program frequency subtraction........Relic default is 24 kHz or there about for its top frequency.  Goldfield default is roughly 40 kHz for its top frequency. If there is something else going on between those two frequency wise, I don't know about it.

[JCR]

I didn't want to reply because I don't use a Deus II but have some familiarity with the question as both the Legend's M3 and the Rutus Versa's Multi W use Conductive Ground Subtraction.  I have made good use of both in certain circumstances. I have even had some improvement with single frequency units by running their Beach mode in 5 kHz.

[broadfield]

There is only one Subtraction process on the D2.

You can get deeper with general in certain wet conditions but this isn't a given, in the addition programs the Notch has the same general effect of the subtraction and would be preferred method of you are after lower conductive targets

[Chase Goldman]

1 hour ago, Jeff McClendon said:

Relic program frequency subtraction........Relic default is 24 kHz or there about for its top frequency.  Goldfield default is roughly 40 kHz for its top frequency. If there is something else going on between those two frequency wise, I don't know about it.

Goldfield uses frequency addition vs. conductive soil subtraction like Relic.  I have yet to set them identically to see if they behave differently on the same max F settings for similar targets on the same ground.

[JCR]

17 minutes ago, Chase Goldman said:

Goldfield uses frequency addition vs. conductive soil subtraction like Relic.  I have yet to set them identically to see if they behave differently on the same max F settings for similar targets on the same ground.

The manual reads like there is a difference between the two types of "Subtraction" on General vs Relic. Being completely different types of Modes it makes sense that the subtraction function would be aimed at a different effect.  Conductive vs Ground response/phase compensation.

[Chase Goldman]

10 minutes ago, JCR said:

The manual reads like there is a difference between the two types of "Subtraction" on General vs Relic. Being completely different types of Modes it makes sense that the subtraction function would be aimed at a different effect.  Conductive vs Ground response/phase compensation.

Understood, I agree that the conductive soil subtraction is probably implemented differently between General and Relic, but I was just talking about whether the two pseudo AM modes (Goldfield vs. Relic) noticeably behaved differently if set up identically since XP made it a point to mention frequency addition for Goldfield (Default Fmax 40 khz) and conductive soil subtraction for Relic (Default Fmax 24 khz).  Never compared them head to head in hot soil with targets at depth and with equivalent Fmax, Reactivity, and Audio response settings.  Won't be able to do that until this fall.

[Jeff McClendon]

4 minutes ago, Chase Goldman said:

Understood, I agree that the conductive soil subtraction is probably implemented differently between General and Relic, but I was just talking about whether the two pseudo AM modes (Goldfield vs. Relic) noticeably behaved differently if set up identically since XP made it a point to mention frequency addition for Goldfield (Default Fmax 40 khz) and conductive soil subtraction for Relic (Default Fmax 24 khz).  Never compared them head to head in hot soil with targets at depth and with equivalent Fmax, Reactivity, and Audio response settings.  Won't be able to do that until this fall.

Chase, did XP change the manual?

My printed copy just says "frequency subtraction" for Relic mode with no mention of conductive soil subtraction.

I don't use Relic much either so I am just learning here. Thanks