I think what we (I) are trying to say is that once I hit a target and it sounds like I want it - I'll hit a few times for a good repeatable signal. Then hit it again standing 90 degrees. By doing so, I can slow down on the sweep and make the sweeps very short side to side over the target. The inner receive coil is only a few inches in diameter. Just by doing this it's easy to see where the target is because of the short sweeps and the response is so fast that I can visually look at the small inner coil and know where the target is. I don't explain things well but I'm trying here. I guess I can say that I can just wiggle the coil in very short sweeps across the target, do it again at 90 degrees, and the areas where the audio signal occurs is so small and sharp that I can see the spot on top of the ground above the target.
Supertune gives additional depth, and when depressing the pinpoint button, there is no low threshold hum anymore because the audio would be coming in full blast. I think Tesoro has the manuals that you can get from their site which would explain it better than I can or someone else can post a better explanation reply to your post.
Anyway I'm new to the Tesoro as I got the Cibola recently and I haven't used it much - but it's already a keeper for sure. Easy to use, works very well, light weight (2.2lbs), sharp discriminate cut-off points, and goes deep. I'm pondering the idea of the Tejon for the manual ground balance and dual discrimination feature - and of course all the nice reviews I been reading. If one must have a screen for additional information, Tesoro has the DeLeon and Cortes. I always work audio first anyway. Most of my machines have a screen which is a nice feature for additional information but I like a variety of machines. When I first started detecting, it was all audio for me, some of the machines I had would have an intensity meter. Then later I got the whites 6000 Di Pro - which I still have, and at that time, that big analog meter blew me away with all that information. But I would work the audio then look at the meter just for additional info, and it was new to me at the time. But I'll keep and use my machines from audio only to the digital LCD menu driven, and this weekend I will use my Cibola and Explorer-II. Seems like a big difference but goes to show the variety I like. Hummm - I wonder - should I go ahead and get that Tejon..... Good Luck