Using SDC 2300 or GPZ 7000 or both?
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GPZ 7000: Threshold Vs Sensitivity Vs Volume Vs Volume Limit (with Discussion On Audio Smoothing, Coil Control, Range Of Motion And Manual Ground Balance)By afreakofnature
Hey All. I have been researching this last month or so throughout Detector Prospector, Minelab's Knowledge Base and TreasureTalks so that I can take my skills with the GPZ to the next level and I think in order to do that it involves these 4 settings: Threshold, Sensitivity, Volume and Volume Limit. A lot of forum members talk about these comparing and contrasting, but none really give you a "How to." How do you go about adjusting these to reach perfection, to reach that perfect ZVT zen.
Conclusions that I have read are that: it just depends on what you want to hear, or how you hear what is coming out of the detector. OK, but I think it is more to it than that, and if you don't understand what these controls do how can you really achieve the best results.
Keeping these setting the same. Noise Canceled. Gold Mode: High Yield. Ground Type: Normal. Ground Balanced with Semi Auto. No filters - Audio nor Ground Smoothing. Lets talk about how we start.
Here is what I have researched and summed up describing these controls. These are my "interpretations" based on everything I have read and I think I really have a grasp on it now. This information and dissemination of it came from everyone here, and I mean everyone! Huge Thank You!
Sensitivity: aka Gain. Control of the INPUT "strength" of a "sound wave." You don't actually control how "sensitive" the coil is. ZVT is ZVT, that is the tech we are using In order to understand these controls I think of it like a "sound wave". What you control is the "sound wave" coming into the machine. Too much gain and you over modulate the sound wave, cause distortion, and increase the "noise" level. Too little gain and your "sound wave" is decreased (like making it a flatter line) maybe allowing large "sounds" to come through but in return lowering the "noise" level and small "sounds." In Sensitivity is where you want to produce the "perfect sound wave" coming into the machine. You want that sound wave to just barely reach below a distortion level to get the best "sound or tone"
Threshold: This is how much of the "noise" level you want to hear. It kind of acts like a bottom or "noise" filter. Increase threshold (lower number on GPZ) and you filter out more of the "noise" level as well as small "sounds." The opposite is to lower threshold (increase number on the GPZ) to filter out less of the "noise" level and hear smaller "sounds."
These two setting should play off of each other so that you can achieve the "biggest window" for the ZVT "sound wave" to operate in with the least amount of "noise". Some people use a 20 sensitivity and a 7 threshold. Is that the biggest window they could achieve? Some do a 15 sensitivity and a 27 threshold. Is that the biggest window they could achieve? How come you could not do a 1 sensitivity and a 53 threshold? Nobody has ever commented on that. Boost it? Probably not a good idea. I don't know, never tried. Food for thought, but I hope you get what I am saying about that.
In my eyes these two controls are where you should start. Achieve the biggest "window" that ZVT can work with. If you minimize the window you are not taking advantage of the full technology. In turn you are probably not finding the smallest pieces you could achieve or the greatest depth on targets. Don't limit ZVT, maximize it to its full potential. Open the window as far as you can for the ground/mineralization you are in.
Now on to Volume and Volume Limit
This is where I do not have the best grasp on these controls, even after all the research I am not sure if I am describing these correct. So many people play off of these and have different explanations. This is what I "think" they mean.
Volume: aka Audio Boost. Control of the OUTPUT "loudness" of the Threshold and Sensitivity window that you just created. We are told that this acts like an audio boost and that increasing this by one is like increasing Sensitivity by 2, etc. I don't think that is a good way to describe it, at least for me. What I think Volume is doing is increasing the loudness of the "window." Than includes the "sound wave" as well as the "noise" associated with it. If you can not hear the targets you want after adjusting your "window" above, then you need to boost the audio. Doing this though will increase what you hear in "noise" and I "think" this is why some describe this as equivalent to increasing Sensitivity but it is not. The "window" has already been set with your Threshold and Sensitivity, what volume does is change the OUTPUT "loudness" and there by multiplies how big the window is ("sound wave" and "noise"). This allows you to hear hear more, but more of EVERYTHING, in affect increasing overall loudness. This is why it should be used "conservatively." Start at 1 and work up until it is where you "like" hearing it. This is the part that should be subjective to each individual and their hearing.
Volume Limit: The Big Mystery. What does this do? How does it help me? Some say that this is actually volume. Some say this is what you should adjust to hear targets better. Some say it is just there to not blow your ear drums off if your volume is set to high. My questions are: Does this affect the "OUPUT" signal or the "INPUT" signal or both? Why would I want a Volume Limit? My thoughts on this...... I think that Volume Limit sets the MAXIMUM Volume (Audio Boost) "level" that can be used. I don't THINK it limits the Sensitivity. So this is an OUTPUT control. Therefore if you set the Volume Limit high you would get a higher (louder) incremental step with each number in Volume (Audio Boost). If you use a lower Volume Limit, you would have lower (less louder) incremental steps in Volume (Audio Boost). So if you want more precise control of your Volume (Audio Boost) you would set a lower Volume Limit. The trade off is maximum loudness. If you need to hear things louder you are going to have to raise your Volume Limit and then adjust your Volume (Audio Boost) accordingly. My thoughts are that people think this actually raises the volume but in the end if you keep Volume (Audio Boost) at 8 and increase Volume Limit, it will get louder per se because you just raised the the maximum loudness level there by increasing the loudness steps for each Volume (Audio Boost) number. Make sense? It does to me, I hope I am right otherwise I am gonna have to relearn this all over again 😉
Well now I need feedback from you all. Am I out in left field on all of this? Am I spot on? Or do I just need some minor tweaks? 🤣
AND if you have the desire to help some, could as many folks as possible make a video of them adjusting these settings to achieve a perfect balance? These are the videos that are missing on YouTube, etc. We see tons of people digging up gold but not many at all on "How" they use and set up their machine. This would be huge to see. You don't have to make a fancy video, maybe just have someone with their phone over your shoulder while you go through it. This would be a huge boon for a lot of people, including myself. Especially us that have to stay in all winter and have to wait to test their own theories. 🤣 So any help in that regard please post! OR if you already found some vids, please share. I have tried every search I could to no avail.
Anyways many members on here have said it before. You need to learn your machine. Its only one aspect of being an expert detectorist. I know I am not there yet cause it sure looks like I am still trying to learn my machine. The rest for me seemed to have come easier, researching locations, reading locations, putting the coil over the gold, etc. Now I NEED to revisit a bunch of locations where I got the easy gold by just using preprogramed settings that I learned when I just started. I started detecting at the SDC level. Turn on and go. I never had a GPX so comparing to the old never helped me. I am part of the new school of detectorists and I don't want to be ignorant by having less control. I want to take control. Its time to achieve ZVT zen and see what was left behind. Its time to level up.
By rob baum
I bought a house in meadview about 4 years ago. Every couple months when I go there I try to get over to gold basin to do some detecting or drywashing. It took me a couple years to find my first nugget out there and its been a couple of years since then and I havent found another. I swing an SDC and I've read people have done pretty good out there with that model. I find plenty of lead and boot tacks a inch or two down but not much deeper than that. What settings are people using out there? How deep down are people finding the gold? Would I be better off with a different model that can go deeper? I'm not very confident in my abilities since I learned this machine on my own and have only found 2 pieces in the 4 years and dozens of times I've used it. Any advice would be appreciated.
By Gerry in Idaho
Here's the 1st video Minelab USA did for TV. You might know the English sounding dude from FL.
What's interesting is we were able to see Minelab Mine Detector as it turned into a gold detector.
The comments towards the end about seeing what's in the ground before you dig it, I'm still waiting.
Do you feel, we'll see a detector that can actually see the item or at least the shape of it with any accuracy and if so how long out?
I have had this problem recently except it happened when switching gold or ground modes. I was switching back and forth to check target signals and lost all audio. It has happened twice and both times i have had to power off the Z to get the sound back. 🤷♂️
I have also noticed that my buttons don’t react that fast. I could fly through the buttons much easier if it would not take a full second or two to switch modes or select things. Is this normal? I have no one to compare this with. I had my GPS fixed under warranty and asked to have my screen changed out since it was scratched, in the process they replaced the front panel, I could have swore it worked faster before they put a new one in. No warranty now.
Maybe a hard restart or factory reset is in order and reinstall the firmware? 🤷♂️
I have had GP machines from the Extreme to the 4500 and nothing has EVER broken despite thousands of hours in the field being banged around, in the back of my pickup and on ATVs over rough trails.
I noticed that my GPZ has started rebooting and loosing it's current setting whenever I lay it on the ground. I have used one of Docs protective covers since I bought it.
I took off the cover and found this:
It appears that one of the pins that holds the battery in position has sheared off likely causing the reboot issue:
Luckily the broken pin was still in my big Minelab protective bag:
I'll try to epoxy it back on and treat the detector as if it is made of glass from now on. I'll admit that I have occasionally let it drop to the ground from a foot or two when going to dig a target. An apparently very bad habit I acquired when using the GPs. No more..
I'll see if I can fabricate a pad for the broken stand since I don't see this part available from ML separately.
I bought the machine used with about 10 hours of prior usage, so no warranty for me.
Just posting this so you guys won't have the same issue.
I’ve done a bunch of research online and I just can’t seem to find this. Does anybody know if there is a detailed video on each of the menu items/settings for the GPZ along with examples in real world environments? I realize that when I’m out in the field now, after continually reading this forum, that I kind of stick to the same settings that I’ve been using for a long time (except for changing between high-yield and general, as well as normal and difficult). It’s winter time, I am bored and I’d like to learn more on my GPZ 🤣🤣. Even if this is not a YouTube video and it’s some thing I can purchase I’d be willing to do that as well!