The variations in sound produced by your detector tell volumes about what is under the ground. The more you practice and learn how to listen, the more proficient you will be at digging the tough, hard to detect targets whether they be deep, masked by trash or iron, or are otherwise difficult to detect.
In today's environment, most good sites have been hunted, and many have been hunted hard. In order to be successful, we must be able to get what others have left behind. In addition to thinking outside of the box, this means that we need to be able to listen for what is left: DEEP signals, and items masked by trash and iron.
By deep, I mean signals outside of the effective ID range of the detector. Often you need to crank up your sensitivity outside recommended levels to reach signals in a given yard, and that means serious degradation of target ID.
Go ahead. Bury a silver dime at 14 inches in your yard. Try to hit it with your usual detector settings. If you can hit it, more power too you - move it deeper until you can't. Now go all metal. Crank your sensitivity up. You can now read it, but it doesn't sound like a dime, does it? If you are on a site that has produced some monsters in the past, and it sounds like a nail but the sound and numbers jump when you isolate with a short wrist-wiggle swing, dig.
Same thing with iron and trash. Heavy discrimination will drive you nuts. Since you can't hear the iron, everything can sound a bit random. Most detectorists in the past have just moved elsewhere. Drop your discrimination and sensitivity, and go slow. Sounds completely different. Listen for high tones, and dig the big iron to get it out of the way. I consistently pick monsters out of that stuff, including my George Washington Inaugural Button , because that is what was left by others. 30 years ago, people could run coin programs and get plenty of stuff and just move onto the next yard. Today is an entirely different ballgame. Take what is arguably my best hunt ever as an example - 3 Civil War belt plates out of a regular size front yard that had been hunted over 100 times:
One of my hunting partners and I that practice these techniques hunt places that have been hunted literally hundreds of times, and sometimes we remark to each other that we are amazed that a certain such place has been hunted at all. And this is me telling you how to do it.
Sound hunting is why it is imperative to wear headphones. You can stay focused from outside sounds, and more clearly hear the nuances of the sounds of the signals. You train yourself to listen - the sound is no longer just a signal telling you to look at the display. The detector's display becomes only a guide. In many Civil War relic hunting instances, I can put one of my machines, an XP Deus, on multi-tone and pop the control box with the display off and put it in my pocket. I don't need it.
If a site has produced several thousand dollars worth of rare relics over the last 30 years, and signals are now fairly scarce, why do I care what number one of the few remaining targets read? Why do I need discrimination when almost nothing is left to be discriminated? Why would I care if cranking up the sensitivity hurts target id?
The best detectorists listen to sound first and only use the display as a reference to assist them in pinpointing and making a dig decision. Plus some deep targets and some in heavy iron and trash may produce only the faintest audible clue. These are easy to miss.
A splatter is a seemlingly random noise in the headphones that you can’t pinpoint. This may drive you crazy. Sometimes it is due to interference from things like power lines, other detectors, etc etc. Try changing channels/frequencies or turning your sensitivity down. The splatter should go away revealing any real signals that are there.