This question will be impossible for anyone to answer in printed text. Because the inherent nature of the question is asking what something *sounds* like. And it's impossible to describe "sound" in printed text. It can only be heard. Not read about. It would be like asking someone: "Please describe the sound of C- major in printed text". Can't be done. You can only hear it audibly to know. That is the limitation of printed text.
You could go to youtube to get accompanying video. But just be aware, that most youtube videos (with "live digs") are not necessarily making their video with the intent on showing what "whispers" are. So ... you may see a live dig, where quite frankly, the signal preceding it was an easy gimmee.
I have seen a few Explorer and E-trac users who made videos WITH THE EXPRESS INTENT of capturing audio for the "deep whispers" of park turf hunting. And show the view the type signal they are trying to isolate. And then show surrounding signals which they are electing to pass.
This may or may not help in your farmhouse scenario. Because I think "depth" and "whispers" isn't necessarily what's at stake there . I think you may just have a location where it's not plush with potential . Ie.: is not mimicking "deep turf park strategy".
If you'd like, I can track down the video(s) I'm thinking of where the guy did an Explorer video (which is like the Etrac), in a SF park, showing shallow clad, vs deep fluty silver/wheatie whispers. That would be a start, for when you leave the farm and angle some old town park commons , etc... in NJ.
A better-way yet, is to simply hook up with a proficient Explorer/Etrac user in your area. Have him flag a few suspected deep silver/wheatie signals in deep-turf environment. Watch the way he wiggles the coil to isolate. Listen to what he's trying to hear. Then you go over the flagged signal and try. From 360*. See how he qualifies "repeatable" versus "flutter". And then conversely, flag a few for him to try and ask him "why or why not?".
And when I say to find a "proficient" user, I'm talking about the guy who routinely comes in with the silver from parks/schools/yards. NOT the sandbox hunter. And NOT the relic hunt guys. Their strategy is a different type "dig all" mindset. Which is fine and dandy for certain types hunting. But for the moment, to get you in the silver-door, I'm talking about the guys who like to ply the parks (where a little cherry picking is sometimes in order), who detest clad (hence might be passing shallow), etc...
This is how the lights went on for me. I'd seen explorer guys spanking me in the parks. So I rushed out and got an Explorer. But ... just like your story, it made no sense. Everything "sounded the same". I heard them "talk about whispers". I'd email and say "what does that sound like ?" Doh! It wasn't till I met up with the guy, had him flag a few wheatie/silver type deep turf signals (at a park where silver STARTED at 7" or more), that the "lights went on". Within 5 targets, I was like a bird-dog on the scent of prey