OhioMike,
Many years ago, (25+) alot of experts in the field had put together a list of their results of what they dug up and the audio responses the detector gave them. This was the time of analog (meter w/needle) detectors and the introduction of the digital age. I have to agree (with the experts) that the most important aspect of detecting is listening to what your detector is telling you, then visual whether, it be analog or digital readout, and last, your decision to dig or no dig. Remember this, pulltabs sometimes overlap with the same readings as gold rings in general. Bottle caps for instance, come in at the quarter to half-dollar range. Yes, I've been stumped alot of times in thinking that I had a quarter but when I dug it up, it was a lowly bottlecap. If you feel that digging up all good targets is the answer, then do so, but if you want to only cherry-pick just coins, it seems that your sen. settings is at where it should be. Try just the coins/jewelry setting or just coins and not zero disc which is an all metal. It looks like you'll be planning on going back to this site this spring. Anyway, here is the list that I compiled over the years from different sources from the experts.
--Listening to the 1st and 2nd Sounds When Pinpointing--
Here are some general rules of thumb for the sounds your detector makes in Discriminate and All Metal (VCO Pinpointing mode). They largely apply to the MXT but should more or less also apply to many other detectors with Modulated Audio.
When you get a loud signal in discriminate mode and the pinpoint signal is loud.
It is usually a large target near the surface.
When you get a loud signal in discriminate mode and a much weaker signal when pinpointing.
It is usually a large target but deeper.
When you get a good signal in discriminate mode and an extremely weak signal when pinpointing.
It is usually a tiny target or a very deep coin size target (from 10 cent to $1.00). Also some Hot Rocks and coal-burnt items mimic this same sound (a little practice in this area helps).
When you get a good signal in discriminate mode and a clear pinpoint signal (average sound).
Then dig . . . This is usually a coin size item at average depth. This is what many of train our ears to.
When you get a weak signal in discriminate mode and also a weak signal in pinpoint.
This is the