Hello Mike,,Great to meet you.I am glad you understand what I was trying to say as I am not up on all the expert term's,Yet I Do put the time in to understand my unit.Exactly as you said,there IS a time and hunting condition one can really reach great depth if they are NOT bound by the depth the display admits.Many when they hunt,they mainly think of location's with much human traffic to imagine anything but using the target ID the unit can reach,to avoid junk digging wasting the day.My friend and I,we hunt anywhere and everywhere.Might hunt 2 hours for that one HIT.,but that one hit end's up a amazing find,more time's than none.In my F5 Manual,it call's the D modes as Discrimination mode 1-2-3-4,,,I never thought to check if that type pitch signal mode as D1, existed in AM mode,Great question..We sometime's just go hunt the wood's.Not as much human traffic,so less junk.Might not dig as much,but when we do,Chances go up for it being a good item.I do know the D2-D3-D4,like "Still Looking 52" mentioned,,hunt's by tone Id-ing the item before breaking ground.For beach's etc,I bet that is best manner to hunt.In another forum I got pounced on,and I dont think they realized what I meant.,lol,.Then I found in the book,Default setting start's at D2,so if one dont manually set their unit in D1,they wont know what I meant.It's the only mode where the Unit dont ID the target by tone pitch. D1,has one tone.The deeper the target,the less the tone.With my phone's,Id hear one little peep,then my heart bounces up in my throat.lol,..I never thought to see if that same method exist's in Am modes..Personally,where I hunt here,I get deep items.I can only speak for what works best here for me in the places I go.I think F5 has many option's.To use the unit's Awesome Brain,it sacrifices depth.The book does say the deeper the item,the less one can trust the Unit's target ID.If I lived in the city,Where I would spend most of my time in spot's with much human traffic,I too would use the units brain.For all I know,Hunting deep stuff,I could skip and miss recent shallow goodies.I am no expert,lol,.But I can tell already,I will like this forum and have a ton of questions for other's using the same unit.I am going out on the weekend,going to be 48 sat and sun.I will see the AM modes..Great meeting you Mike.