There are three basic types of metal detectors on the market. Pulse detectors, motion detectors and multi-frequency machines - the newest kind. Motion detectors are best used on land and in fresh water. Pulse detectors work best in salt water. Multi-frequency detectors are a newer, more pricey technology, but they're also the most flexible. They work in nearly every condition.Other things to think about are whether you'll want a waterproof device, or if a land machine will be sufficient for you. Several land machines are extremely sophisticated. They can even tell you what they've found before you dig!Water machines, on the other hand, don't offer these types of sophisticated features. They do, nonetheless, allow you to walk in shallow water or even immerse the machine.Whilst serious hunters used to have to own two or three different metal detectors for particular jobs, one good quality multi-frequency, waterproof machine can now do it all. You get what you pay for when it comes to metal detectors.A cheap machine may not dent your budget to a great extent, but it also doesn't penetrate deeply into the ground. That means you'll more often than not find unwanted items.Spend a little more for a high end detector, and you'll be finding more deeply buried items - that translates to a higher likelihood of finding something worthy.Good metal detectors can stumble on items at least a foot beneath the surface of the soil, though the exact depth will contrast by object size, soil composition, metal type and other factors. That's because dirt with a high mineral content can decrease depth and increase interference.That means that when you decide which is the best machine, you should start out by looking at the setting you'll be utilizing it in.If you only aim to look for relics, or if you live in the American Southwest, a waterproof machine won't do you any good! Consider about what you're looking for, too. There are machines that do well with silver, but not with gold, for instance.Once you discern what you're looking for and where you're most likely to conduct your hunt, it's time to think about some other vital features. Ask yourself how deep you need to search.Decide what kind of target alert system you want, too. Some machines have different beeps, depending on what they've encountered. Can you correct for the kind of soil? A few will let you to manually adjust for minerals, or will even do it on their own.There are also metal detectors that allow setting changes for different object types, and allow you to adjust sensitivity to avoid picking up as much junk. Displays vary, with more complex types giving you additional information. Check battery life, as well as size and weight.While most detectors are just several pounds, they can still feel heavy after a while. Most machines use AA batteries, but battery life varies widely. Other valuable features contain collapsible shafts, versatility in water types, improved sensitivity to valuable materials and the ability to rule out garbage.Of course, funds will be a factor. When you understand what you need from your metal detector, you need to look at how much you can spend. It's best not to settle on features. Have a small budget but require a good detector? Think about buying used!