John-Edmonton
Silver Member
- Mar 21, 2005
- 4,399
- 3,950
- Detector(s) used
- Garrett- Master Hunter CX,Infinium, 1350, 2500, ACE 150-water converted 250, GTA 500,1500 Scorpion, AT Pro
But.....How Deep Is That Metal Detector?
First of all, it's very difficult to answer that question, if not impossible. The answer really is "it depends"
The following all play a significant role, and in combination will always give varying results:
-size of a target-> the larger the target, the deeper a target can be recognized.
-conductivity-> aluminum vs. copper vs. gold. vs. iron vs. silver. Some rings, with size & mass being equal can be detected deeper then others.
-size of coil-> general rule says "larger coil = deeper depth however, add a lot of conductive particles, metal junk and high mineralization to the matrix, and the large coil becomes redundant.
-type of coil-> DD vs.concentric vs. mono. Each coil has a definite advantage over the other under different conditions
-frequency of signal from coil-> higher frequency usually (but not always) is more sensitive to tinier objects.
-VLF vs. Pulse Induction-> Pulse induction can easily pick up a dropped mini or gold ring with a medium sized coil 15-20" whereas a VLF might get about half that all other things being equal.
-Humidity, moisture in soil, orientation of target to the coil
--ability of the coil to perceive the receiving frequency from a coil and distinguish it's conductivity, depth, size etc.
-operator - properly setting up the electonic components based on knowledge and experiences
There are many more variables in involved affecting depth.....the above are just some of the more obvious ones. So really, YOU need to figure out what you are looking for ie. relics vs. jewelery vs. common coins vs. deep copper/silver coins. You also need to know the soil conditions and other factors in YOUR area where you are going to hunt. Lots of electronic interference from above ground or below will make some of the most expensive machines useless, unless you turn the sensitivity way down, which often times reduces your depth considerably. Same goes with extremely high mineralization like in Australia or red clay oxidized clays in North America areas. VLF may really struggle under these conditions, yet a PI (pulse induction) will punch down deep with no trouble.
So.....how deep is the Pro? It is as deep in some instances and deeper in other instances and perhaps not as good as machines costing sometimes more then twice the cost of the . Throw on the 9 x 12 concentric coil in good ground and you have a very deep detector with great ID capabilities. Use the DD 8.5" x 12" coil in heavier mineralized soil, and it outperforms even the larger coil I just mentioned. Put on the 5" x 8" coil and you can easily pick out the good targets beside and often time underneath junk targets, while still getting great depth.
You want a simple, cost effective yet very productive coin/jewelry hunter Garrett has it - Garrett EuroACE Metal Detector | Manufacturer
You want a machine for caches buried in feet, not inches - Garrett has it - Garrett's Searchcoil Tech Sheet | How Searchcoils Work
You want extreme depth for water or land, check out the Garrett Infinium - Garrett Infinium LS Metal Detector | Manufacturer
You want a great all around machine for good depth + Salt or freshwater hunting (waterproof) Check out the At Pro - Garrett AT Pro International Metal Detector | Manufacturer
You want to search for gold nuggets both tiny and large, check out the Garrett ATX - http://www.garrett.com/hobbysite/hbby_atx_main.aspx
You want to hunt common coins with sizing ability, check out the GTI Series- Garrett GTI 2500 Metal Detector | Manufacturer
Why should depth not be the most important factor for purchasing a metal detector? Because depth is only relative to certain conditions. Most targets are in the top 6 inches anyway, so why do you need to go down to 15-20"? In places like salt water or areas with a lot of deep junk rusty targets, the large coil on your $1,500.00 machine is practically useless, and when set up to it's maximum potential in these areas, will only give you say 4-5 inches. If somebody is trying to sell you an expensive detector, that they say is the deepest machine, you had better turn around and run fast....as that equates with someone trying to sell you a a parcel of land in a swamp. There is no 'DEEPEST" machine....it simply doesn't exist. But there are BEST configurations of a metal detector type for any given matrix of soil.
Choose wisely!
Page from an earlier Garrett Metal Detector Catalog....
First of all, it's very difficult to answer that question, if not impossible. The answer really is "it depends"
The following all play a significant role, and in combination will always give varying results:
-size of a target-> the larger the target, the deeper a target can be recognized.
-conductivity-> aluminum vs. copper vs. gold. vs. iron vs. silver. Some rings, with size & mass being equal can be detected deeper then others.
-size of coil-> general rule says "larger coil = deeper depth however, add a lot of conductive particles, metal junk and high mineralization to the matrix, and the large coil becomes redundant.
-type of coil-> DD vs.concentric vs. mono. Each coil has a definite advantage over the other under different conditions
-frequency of signal from coil-> higher frequency usually (but not always) is more sensitive to tinier objects.
-VLF vs. Pulse Induction-> Pulse induction can easily pick up a dropped mini or gold ring with a medium sized coil 15-20" whereas a VLF might get about half that all other things being equal.
-Humidity, moisture in soil, orientation of target to the coil
--ability of the coil to perceive the receiving frequency from a coil and distinguish it's conductivity, depth, size etc.
-operator - properly setting up the electonic components based on knowledge and experiences
There are many more variables in involved affecting depth.....the above are just some of the more obvious ones. So really, YOU need to figure out what you are looking for ie. relics vs. jewelery vs. common coins vs. deep copper/silver coins. You also need to know the soil conditions and other factors in YOUR area where you are going to hunt. Lots of electronic interference from above ground or below will make some of the most expensive machines useless, unless you turn the sensitivity way down, which often times reduces your depth considerably. Same goes with extremely high mineralization like in Australia or red clay oxidized clays in North America areas. VLF may really struggle under these conditions, yet a PI (pulse induction) will punch down deep with no trouble.
So.....how deep is the Pro? It is as deep in some instances and deeper in other instances and perhaps not as good as machines costing sometimes more then twice the cost of the . Throw on the 9 x 12 concentric coil in good ground and you have a very deep detector with great ID capabilities. Use the DD 8.5" x 12" coil in heavier mineralized soil, and it outperforms even the larger coil I just mentioned. Put on the 5" x 8" coil and you can easily pick out the good targets beside and often time underneath junk targets, while still getting great depth.
You want a simple, cost effective yet very productive coin/jewelry hunter Garrett has it - Garrett EuroACE Metal Detector | Manufacturer
You want a machine for caches buried in feet, not inches - Garrett has it - Garrett's Searchcoil Tech Sheet | How Searchcoils Work
You want extreme depth for water or land, check out the Garrett Infinium - Garrett Infinium LS Metal Detector | Manufacturer
You want a great all around machine for good depth + Salt or freshwater hunting (waterproof) Check out the At Pro - Garrett AT Pro International Metal Detector | Manufacturer
You want to search for gold nuggets both tiny and large, check out the Garrett ATX - http://www.garrett.com/hobbysite/hbby_atx_main.aspx
You want to hunt common coins with sizing ability, check out the GTI Series- Garrett GTI 2500 Metal Detector | Manufacturer
Why should depth not be the most important factor for purchasing a metal detector? Because depth is only relative to certain conditions. Most targets are in the top 6 inches anyway, so why do you need to go down to 15-20"? In places like salt water or areas with a lot of deep junk rusty targets, the large coil on your $1,500.00 machine is practically useless, and when set up to it's maximum potential in these areas, will only give you say 4-5 inches. If somebody is trying to sell you an expensive detector, that they say is the deepest machine, you had better turn around and run fast....as that equates with someone trying to sell you a a parcel of land in a swamp. There is no 'DEEPEST" machine....it simply doesn't exist. But there are BEST configurations of a metal detector type for any given matrix of soil.
Choose wisely!
Page from an earlier Garrett Metal Detector Catalog....
Last edited:
