coil compatability with GPX 4500

Hi all
Being a newbie I will, unfortunately, have more questions than answers concerning gold prospecting. I believe that the best way to learn is to talk to those who know more, and for that reason among others, I have joined the forum. I am using a GPX 4500 and at present have 2 coils only, an 8 inch minelab goldsearch mono and standard minelab 11 inch DD. I would like to get a bigger coil to punch a bit deeper on some grounds, preferably the next beneficial size after the 11 inch. Can anyone recommend or advise the coil types that are compatable with the 4500. Minelab obviously recommend their coils and suggest perhaps that some aftermarket coils (which coils constitute aftermarket???) can create extra battery drain, and may not perform with 100% sensitivity. The used coils that I most frequently encounter are the red brown type coiltek coils. They are generally cheaper too, does that mean you get what you pay for or are they compatable with the 4500 and provide optimum performance? Any assistance here will be greatly appreciated. Cheers

UFO

With the GPX series it is better to stick with the later model coils from the various manufactures, this is for two reasons, firstly the older a coil gets the more noisier it will become assuming it has seen constant use in that time frame this is due to flexing in the housing which then degrades the shielding causing noise, the second reason is the later minelab machines need better manufacturing processes and closer tolerances to work well, something the older coils will not have due to the design parameters required by the detector that was in vogue when they were made (Minelab coils included).

So the coils to look at for a GPX-4500 are any of the Minelab Commander coils, Nugget Finder Super Lights (SL) and Advantage SL and the Coiltek GoldStalker Monoloops or DD Pro coils.

Hope this helps,

JP

Hi JP
Many thanks for your interest. The info you provided is a huge help as I have been quite concerned about coil selection since purchasing the machine. Being a little more informed, I can now forge ahead with some confidence and select a suitable coil, most likely a minelab commander coil. The next hurdle, although relatively minor, is whether to choose DD or mono and which size. Probably DD as it would, I presume, provide more options with this machine, and maybe size 15x12? Cheers

UFO

Actually a Monoloop would provide more options with the 4500 considering you already have a decent DD coil in the 11" that came supplied with the detector. To take advantage of the new timings of the 4500 a Monoloop coil is the only choice as they are optimised for a Mono (eg Smooth timings and Enhance). The other benefit of Monos is they are much lighter than a DD due to less wire inside thanks to only a single loop around the outside edge whereas a DD has two windings crossing each other in the middle.

Might I also suggest you take a good look at the 11" Minelab Commander, they are an excellent coil and are no where near as heavy as the 15" elliptical but provide nigh on the same overall depth thanks to the round design. The Minelab coils are quite a bit heavier than the after market varieties but more than make up for the shortfall by being made by the manufacturer so you know straight up they are within design specs so all functions of the machine will work correctly and secondly are very competitively priced, with the addition of a HipStick the coil weight issue can easily be solved making for a good detector/coil combination.

Hope this helps,

JP