Barely Audible to Silent Threshold

[landman]

I'm puzzling over the threshold level issue people are talking about on the forum. Clive in his books tell an interesting story I'll try to articulate with my own experiences on the Excalibur. Let me set the stage here for discussion.
First there are 3 threshold sounds on the Excalibur when the threshold is set to audible, that means a sound comes through your headphones before a target is encountered. when a target is present hear are my observations of what can happen 1.) The threshold can silent when going over iron 2.) The threshold can growl or rough sounding which you get when going over iron and it gets done nulling and then it produces this louder rougher sounding growl buzz or hum after the null ends and you hear the threshold again. 3.) The fainter threshold sound you get when either you turn on the machine or go over a deep nonferrous signal too to sound off.

Now here are some observations.
A.) The growling or rough sounding threshold is louder respectively to the threshold you get when you turn on the machine which I'll call the nonferrous threshold. So that means if you want to hear all the thresholds you have to put up with a necessarily louder than acceptable iron growling threshold to hear the nonferrous threshold. And if you turn it down low enough that the growling threshold is almost silent then the nonferrous will be silent till you get a non ferrous signal from a target you just swung over.
B.) The nonferrous threshold sound is supposed to be a high or low pitch sound based on the type of deep or off centered metal target you just swung over. So if the threshold is a growling sound just after going over iron and all of a sudden you get the less audible low hum threshold, you probably just went over a pull tab or gold ring. A higher pitch sound, then a coin.
C.) A very deep nonferrous object can null like iron. When the coil is passed over and it does not give a nice repeatable sound or even give us a faint non ferrous threshold that tells us to re-swing over that spot, it might just null like a piece of iron.
That means in certain hunting conditions like my 1920's beach each null or change in threshold tone is a cause to stop re-swing and possibly dig.

Now here is what I do not understand. If each threshold sounds, nulls or changes in tone tell us something about the target in question your coil is over, then why would you hunt with the threshold just below silent. If you are to hunt in silent mode then you cannot: Hear it null and question if it is a deep nonferrous target. Hear the threshold change in tone to tell us a deep keeper might be present. Hear it growl to let us know that that null was probably iron below it.

What say you?

 

[JohnA]

n/t

 

[JohnA]

listening for threshold changes and reswinging. This method worked for me, but the barely audible to silent threshold setting seems to be producing more frequent and deeper targets or I have been on a fairly long lucky streak. I am going to continue to hunt this way. BTW, I have redetected spots several times with my Infinium and not found any good targets. Last year, with the Excal in low threshold but hum mode, redetecting with the Infinium also produced no good targets, but I always found nickels, which made me worry about missing gold. Now I found nickels just about every trip. Pulltabs have never been a problem. I agree with you. It is confusing, since I have read the threshold change may very well mean a deep target. I guess I should turn the threshold up after I detect a target and see what happens when I am having a slow day. Topics like this are what make this a great hobby. Good luck.

 

[gold-digger]

As much as I would love to find all the gold, digging every sound that you might hear would wear you old fast. Hunting 50-100 year old beaches just means that there is that much more potentially junk filled areas to dig. Sure the finds may be there, but you'll have to clean the area first of all the cans, pulltabs, caps, etc.

On another note, I've met plenty of hunters out ther that will say a beach is hunted clean and others that will fine search it in pinpoint mode or high threshold and pull up chains and others goodies.

Just my input...

 

[Gulf Hunter]

I do not pay too much attention to the threshold tone, except when I hear the high pitched strained tone, that cjc warns about where the, "unit is not dealing well with the ground". When this pitch is heard, then I get concerned and turn the sensitivity down, till she calms back down. When hunting silent, this tone is harder to hear, so I HAVE been running it VERY quiet. If the threshold tone appears back through the headphones, I turn it back down. It is working for me, but I am always fiddling with the knobs and learning new things about the Excal. The learning process is always being refined on the Excal, ever since I started using it in Jan. '06. My advice would be to try it both ways and see which way outperforms the other.

 

[landman]

I guess I do not fully understand the technique, its purpose or point. let's first see if I understand the correct setting for "silent threshold mode" that the knob is set just below sound, where all possible thresholds could sound. If I hear any threshold peeking over the setting then I need to turn it down just a bit. Do I have the setting correct?
If so please explain the advantage in this silent setting.

 

[bottlebum]

If I were running silent, two things I would never know are, if the threshold adjustment were to drift further below the (just silent) setting or if the knob were to get bumped causing the threshold setting to go lower than intended. This could cause very faint signals to not be heard. Plus, you would never hear the nulling of the machine over a discriminated object nor the returning threshold tone of the discriminated object, some of which might not be junk. Just a thought....
HH, bottlebum

 

[bdahunter]

I'm running my Excal at 10:30 to 11:00 on sensitivity and threshold at just below audible. The threshold has a habit of creeping back up into audible over time so I have to readjust it below audible. I hear very faint signals when in silent mode and these invariably mean deep digging. Mineralized areas are virtually non existent in my area because of the local geology so no worries about that.

Cheers,

BDA

 

[Gulf Hunter]

You are apparently curious or you wouldn't be challenging the method. Just try it and if it sucks, do it your way. I will take you down the housing, but skip around a bit, savvy? Run it this way and get the gold or do it your way. Discrimination 1, Disc, Volume wide open, Sensitivity (6 Excal II) (12 Excal I). Threshold barely audible, then down to just not audible. If you are concerned that the unit is not dealing well with the ground, turn the threshold up to barley audible and see if the high strained tone is heard, if so turn the sensitivity down a hair, until the unit comes back into the low or mid toned humm, savvy? I am not out to sell the method, do it your way, but you'd better be sure you're right.

 

[Lou from downunder]

Hi guys,

I'm not knocking the silent threshold method but....

Is the suggestion that by running in silent we are suddenly hearing the faint deep targets that null when operating in audible?

Cause if in audible we are digging signals to the point of the faint null, then to get more {deeper} good targets in silent, these deep targets that faintly null in audible must be now sounding off and not nulling, otherwise you would not know they're there.

Or... maybe in silent the machine for some reason detects {sees} more targets at normal operating depths than in audible, and the deep targets {unfortunately probably gold} continue to faintly null, but we just dont know cause in silent you cant hear a null.

Or...is the theory that a faint null in audible is a good deep target a load of crap?

Cheers Lou.

 

[landman]

then it would help me learn. Thanks.

 

["MR. GOLD MASTER"]

I Think that hunting with a silent threshold is good method to hunt in!!!!!
Every one should give it a try because you might end up being very satisfied with the way this method works. Think about all the time you can save by not having to do the sovereign wiggle much any more because you wont hear any of those annoying null outs and threshold changes that could indicate iron junk or the presence of a good deep gold target in the fringe. Now if more folks could just implemented this method of hunting there would definitely be lots more deep gold for Me.
Yes in all seriousness it can be a good method to hunt in during the times that the detector is constantly nulling out and threshold changing due to severe ground conditions that are present in the soil.

 

[landman]

I see. This morning I tried the silent method. But it was in a trashy old beach from the 1920's. I was not distracted until something came through and then I dug. However I do not see the advantage of hunting silent in a non trashy area
or if the ground is bad. I also had the sens. on auto because of the amount of trash and iron sludge, burnt coal I think and the targets were not deep.

 

[JohnA]

on another Forum, in which the poster says he dug all the nulls when he first got his Excal and they were always iron. If the null was followed by a weak signal, then a non -ferrous target was found also. One detectorist's observation. I also dug a few nulls at first when targets were rare, and they were always iron in my case too. This topic does have many facets and there are lots of variables and most detectorists are still learning subtle nuances about the Excal. At this point I tend to agree with suggestions 1,2 and 4. I am going to continue to hunt with barely audible or silent threshold for now as it seems to work better than a constant hum for me, but will do some experimenting with the threshold settings, gridding and a redetecting an area at the end of a hunt. Will probably hit the same area with my Infinium as it doesn't null on anything. I have done that before on a few occasions and have sometimes found more clad, of course iron, but no jewelry. If I come to a valid conclusion that can stand up to reason, I'll let you know.

 

[Gulf Hunter]

OK, I consider "MR. GOLD MASTER" to be a foremost authority on the Excal and he does not say much, but when he does, you'd better listen.

 

[Gulf Hunter]

Landman, I recently went 27 straight hunts, without a piece of gold. The period began in early December '07 and did not break until March '08. During this period, I was not only running a CZ21-10, but also experimenting with Auto on the Excal. I will warn you now, that Auto is a TERRIBLE choice. Figure out how to make the unit get peak performance OUT of Auto, it's a LOSER! I'LL NEVER USE IT AGAIN! I was in a hypertrashy area, when I came to my senses and switched back out of Auto and almost IMMEDIATELY began recovering deep targets again. Targets, that could NOT be heard at all in Auto. Don't go there and consider yourself warned mate!

 

[therover]

Auto is not the way to go. Learn how to run the sens as high as you can while stable. When the Excal starts to act erratic, back the sens down a tad. Don't go into Auto.

As far as the silent threshold goes...I have to give that a try. I always run barely audible...never a loud hum, but the silent threshold bit is intriguing.

JC

 

[Lou from downunder]

I'd been lurking on the forum for months before I got my excal, reading and learning all I could before taking the plunge.
Read with interest the various posts on running in silent, was impressed with GH's staunch support of this method. If memory serves me correctly, and it often does'nt, I believe it was CJC that alerted him to this method in one of his earlier books on the sov and excal?
If so, then I was mightily surprised to find no reference to silent running in his excellent publication, " Advanced Methods For Finding Gold etc". In it there are constant referrals to threshold, how it should sound, how signals enter and leave it, nulls etc.
Regardless, it seems to be accepted by most that he is an authority on the excal and if in Advanced Methods etc he advocates threshold audible, then why are we running in silent?

Dont get me wrong, I like silent. Its far more relaxing, no need for intense concentration, take in the scenery, both above and below, and only put the brain into gear when a target sounds.
But is'nt this the lazy mans way of detecting?
I know that some claim to be finding heaps more in silent, but are they double checking in audible before they dig?

I read on the X Terra forum a while back that too high a threshold will definately lose you targets so this is obviously an issue that affects most detectors, with low being the way to go.
But silent? Hmmm.
It does make you wonder.

CJC, you out there? What say you?

Cheers Lou.

 

[Neil]

the deepest targets only change the threshold and turning it down so you cant hear it may be less bothersome but certainly doesnt aid in getting deeper targets.

CJCs books are great, but minelab makes their recommendation of using the threshold(and providing it on their detectors) for a reason.

so you take your excal/sov and hunt along in a low threshold, just audible but nice and steady and you come upon a target that just moves the threshold.......a slight pitch change.........then turn the threshold down so you cant hear it and see if you get the target.........try this a few times and you will know which is better.

HH
Neil

 

[landman]

with that logic. I tried the silent mode and found it pleasing. I could just swing and not focus or hear anything till a bling or blip materialized. Then I could go into investigator mode and go to pinpoint and evaluate it. It was very relaxing. However apart from that or using the silent method for heavy iron infested sites, I have yet to hear a logical answer other than to, "try it." Objective, empirical information is what I'd like to hear. So if I'm in an iron infested area with shallow targets or I need a mind break then I could and would go silent, but otherwise I do not see an advantage only disadvantage.