It has two discrimination controls yes! but they do not work at the same time, nor are the really hooked to one another. They can be set independently from each other, usually disc one is considered as primary and disc two secondary and setup this way the disc #1 may be set to a lower point then disc 2 may be set to some higher point. Lets say your hunting for coins (US coins) you might set disc #1 to the edge of nickels dropping out, then set disc #2 to just above screw caps, things below nickels are knocked out and you get a pretty good hit that's above the scratchy nickel sound, then you push the finger toggle forward to switch to disc #2 and the target is still solid, that tells you that the target is in the upper range for the clad, copper, or silver coins, but if you toggle to disc # 2 and the target goes silent then its not a coin signal.
Now, as for control settings of all metal!
There is ONLY one control (knob) that selects ALL-Metal and that is the discrimination controls! both disc # 1 and disc # 2 has the ALL-Metal option, but this isn't two different ALL-Metal modes, its the same mode.
The only other ALL-Metal mode is selectable by the finger toggle below the control housing!, this is referred to as the "Pinpoint All-Metal" mode and can only be activated my the momentary pull of the finger toggle, so to search in this mode the finger toggle would have to be held in place!
And, yes! at max discrimination some depth is lost, but in normal (average) soil its not a LOT!, but in hunting coins there isn't much need to hunt above screw caps, but if your thinking you can hunt at MAX disc and it hard on a silver dime @ 10 or more inches its just not going to happen. Few even thousand dollar detectors really can. The true working depth of MOST very, Very! good detectors in average soil is 10" or less (and 10" REAL inches is the MAX) now larger stuff that relic hunters may dig up could be deeper.
All-Metal Search, and
All-Metal Pinpoint
A high setting of one discrimination control doesn't effect the other, the yes, if disc two is set to max and you toggle to it, there may be of depth difference of the disc, but when you toggle back to disc one you would just jump back to the lower setting and the depth gain of that control.
And No! there is no controls or settings for sweep speed.
Mark