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  1. There are a few key things to know about headphones for use with metal detectors. The most important thing is to know that some detectors operate in mono, and some in stereo. If you mismatch headphones you can end up with audio in one ear only, or none at all. In fact, this has happened to me. I took my White's DFX out to do a little detecting, and grabbed an old pair of Fisher Phones I had around, and when I got out I found the phones would not work on the DFX. So most detector phones have a stereo/mono switch, or are specially wired to work either way. Make sure your headphones match your detector for stereo or mono operation. But best case is to only use headphones that can do both so you can use them with any detector. You never know when they might get put to use on a different machine. In a situation where you are determined to use a mono headset on a stereo detector or vice-versa plug in adapters can be purchased at most electronics supply houses. 99% of the detectors out there have a 1/4" headphone plug, but many generic headphones have a 1/8" plug. Sure, you can use an adapter, but it just adds a weak spot in the system. So get a 1/4" plug unless your detector is one of the rare 1/8" models. Again, pay attention to the mono versus stereo issue. The good news is that if you make a mistake there is almost always an adapter that will fix the problem but it is best to try and get the correct match. Does your detector have a volume control? Many do not. It is best to buy headphones that have their own volume controls, so you can use them with detectors that do not have a volume control. Again, you never know when you might switch detectors. Ohm matching can be important, and generally higher ohms is better. This is not always true however and some detectors do work better with lower ohm rated models. It is usually easy to determine what the headphone ohm is but almost impossible to know what the detector rating is. I therefore recommend that you should have your detector in hand and be trying the headphones before you buy them instead of going by specs on this point. Things to look for: 1. How do they sound? Are targets sharp and clear to your ear? If not, you can now pass on this set and try another. Different headphones match up with different machine and different ears in such a way that nothing short of trying them can sort this point out. They either sound good to you personally, or they do not. It does not matter what your friend likes. Some detectors allow you to change the pitch from high to low. Try different pitches with your detector to see what sounds best. How do faint targets sound to your ear? People have different frequency responses, some like low tones and some high, and the type of speaker wired into the headphone can make this sound vary a lot. Get a set of headphones that make faint signals as clear as possible to your particular ear. 2. Assuming they sound good, how adjustable is the volume? A good match will give you the ability to fine tune the sound with the volume control on the headphone. In other words, the volume control will have some range. If you have very high ohm headphones and use them on a high volume machine that has no volume control, the headphones may be so loud you have to set the volume on the headphone nearly off. And then tweak it within a fraction of a turn. Some headphones are too powerful for some detectors! The volume control should run from off at one end and too loud at the other, with lots of adjustment in between. 3. How many volume controls are there? Some people like two, one for each ear. This can be great if you have poor hearing in one ear and need to compensate. I personally prefer a single control that works both ears at the same time, so I do not need to fiddle two controls. So this is a personal preference thing, but your headphones should have one or two headphone volume controls. A note on setting your headphones. Turn the detector volume all the way up, if it has a volume control. Turn your headphones all the way down, then turn on your machine and wave it over a large metal item. Turn the headphones up until the loudest sound you will get over a large item is not so loud as to damage your hearing. Now, set the threshold sound on your detector for a faint buzz. You should now be able to hear faint variations in the threshold, but going over a 55 gallon drum will not damage your hearing. Metal detector headphones showing 1/4" 90 degree jack, coiled cord, padded muffs, and dual volume controls 4. How well do the phones exclude outside noises? Normally, get a set of headphones that will exclude outside noises like running water, wind in the trees, or anything else that might distract you from the detector sounds. Sometimes it may be advantageous to use phones that let you hear outside noises, like in bear or snake country. Or maybe in real hot climates bulky units get too warm. But from a pure detecting standpoint sound excluding headphones are best. Earbuds are perfectly acceptable however for quieter locations. 5. How well do the headphones fit and feel? Imagine they are going to be on your head for 12 hours. Something that feels good initially can feel pretty bad in a few hours. Beware of headphones that are too tight or that have too little padding. I prefer phones that completely cover my ear and seal to the side of my head. I do not like the kind that squash my ear but people's preferences vary. Make sure your headphones are comfortable for long hours of use. 6. How tough do the headphones appear to be? This can be hard to gauge sometimes, but in general avoid anything that looks to have cheap construction. The number one failure point is the cord, so make sure it is strong and well anchored so it cannot pull out. Headphones that feature a 90 degree plug are often desired to reduce strain and prevent the plug from pulling out due to a simple tug on the cord.Some top end models feature replaceable cords so you can carry a spare. I prefer to simply carry a complete spare set of headphones. 7. Finally, be aware that the newest metal detectors are coming equipped with built in wireless headphone capability. Early versions have either been standard Bluetooth, which is too slow, or some faster proprietary method. Standard Bluetooth has a significant lag between detecting a target and the actual audio response heard in the headphone which is bothersome to most people. The problem with proprietary is that you are stuck with very limited options as to headphones. The best option currently for most people is aptX Low Latency (aptX LL) Bluetooth, which is fast enough that most people are satisfied with the speed, and options abound in the choice and style of headphones. To sum up, if buying headphones at Big Box Inc. at the least you'd probably want a set with a stereo/mono switch, 1/4" jack, and volume control/controls just to make sure it will work on most any detector. But remember that headphones are like tires for an expensive sports car. They are one of the only important items on a detector you can customize for optimum performance, the other being search coils. Finding the set of headphones that is just right for you can make a real difference in detecting success, so it deserves some effort in getting the right set. This is where a local dealer with a good selection who is willing to let you try them all out on your detector can really help you out. ~ Steve Herschbach Copyright © 2009 Herschbach Enterprises
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  2. Unseasonably cold weather continues in Southcentral Alaska. The snow at Crow Creek Mine was still 1-2 feet deep Saturday morning, and minor amounts of snow were actually coming down as I arrived at the creek! The good news is that if it was warmer, then the snow melt would cause the creek to be higher and muddier. Even with the cool weather, the creek was up slightly and a little murky, as the photo above shows. The creek did completely open up over the week, and the snow bridges are all gone now. My dredging was rather uneventful this weekend, and a little on the short side time-wise. I wanted to get home a little early each day because of Mother's Day (good idea to let my wife know I do exist) so I got in about 5 actual hours of dredging each day. This was okay on Saturday, as I picked up a little coarser gold and still managed to get about an ounce. The short hours worked caught up with me Sunday. I was approaching a small set of rapids with some fast moving, boiling water. The creek was widening slightly at this point, so I decided to tackle the fast moving water by diverting the water to the right and then working up the left side. You can see the small diversion dam in the photo above at the head of the dredge excavation. The idea is to work a channel up the left hand side, then divert the water into the new channel. The material on the right hand side of the creek may then be worked, without having to deal with the fast moving water. Unfortunately, I worked outside the paystreak somewhat, which is more or less centered on the middle of the creek along this stretch. I only picked up .7 oz. Sunday, short of my normal daily goal of 1 ounce. If I had put in that extra couple of hours, I no doubt would have made my goal. This puts the total for the weekend at 1.7 ounces, and the 5 day dredging total 5.8 ounces. I'll have to work my regular hours again next weekend to move the average back up. 1.7 Ounces of Gold from Crow Creek So where is all this gold coming from? The ultimate source is a group of historic hardrock mines at the head of Crow Creek valley, discovered around 1909. Two of these, the Monarch and the Jewel mines, produced a total of about 5,000 ounces of gold by 1947. These mines consist of thin irregular quartz veins carrying arsenopyrite, chalcopyrite, galena, sphalerite, pyrrhotite, molybdenite, pyrite, magnetite, and of course, gold and silver. This is a common type of gold ore in Alaska, in that it has a little bit of everything... gold, silver, copper, lead, zinc, iron, and arsenic. The veins are in the graywacke and slate bedrock typical of the Kenai peninsula, are are grouped around some small quartz diorite masses that intrude the surrounding bedrock. The mines do not seem particularly rich, but are listed as having a high mineral potential by the former Bureau of Mines. Gold eroded from these and other gold-bearing veins was deposited in Crow Creek, mostly before the last glacial advance. Crow Creek is very unique, in that the advancing glaciers did not totally disperse the gold deposits, but instead buried them and left much of the old deposits intact. The original miners on Crow Creek discovered the presence of several deeply buried canyons, and excavated most of these. These deposits were very rich, with material with up to 6 ounces of gold per yard of gravel recorded. A yard of that gravel discovered today would be worth almost $2000. (2011 Update: Over $10,000!) The original bed of Crow Creek exists as a dry channel directly below the Crow Creek parking lot. The creek is now flowing through one of the old excavated channels far lower than the dry channel. Over 250 feet of material was removed to excavate the old channels. Despite the visions of environmental havoc this may cause one to imagine, the excavation has fully grown back such a profusion of trees and other vegetation that most visitors believe they are standing in a natural valley, not a large man-made excavation. The upper portion of Crow Creek Mine has many exposures of virgin gold-bearing material on both banks of the creek, as well as tailings redeposited along the creek itself. This area is open to the general public for a fee and produces the larger gold nuggets found at Crow Creek Mine. Nuggets of up to 1/4 ounce are fairly common, with nuggets of up to 1 ounce sometimes found. The largest nugget recorded from Crow Creek weighed 3.37 ounces. Almost all the nuggets found with metal detectors come from the upper area. I have found thousands of nuggets metal detecting in the upper area, the largest weighing 7 dwt. and numerous 1-5 dwt. pieces. The old canyon on the lower claims where I am dredging was mostly mined out, but the waste material form the upper workings was dumped into the canyon. Gold was lost in the tailings due to the large volume nature of the hydraulic mining methods used, and the gold has been concentrated by floods over the years into workable deposits. The gold is more consistent then in the upper areas, but overall of a much smaller size. Larger nuggets are very rare in the tailings, although I did find several, including a beautiful 1 ounce specimen last year. I do find pieces of up to a pennyweight on a regular basis, such as the one in the photo above, in the canyon material. 1 Ounce Nugget found at Crow Creek in 1998 by Steve Herschbach ~ Steve Herschbach Copyright © 1999 Herschbach Enterprises
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