What, in your opinion is the best dedicated relic hunting machine? Light as possible, no bells and whistles, except great depth 9-10" on a minnie ball, 12-14" on a plate. Manual ground balancing, adjustable all-time capable threshold, good tonal seperation (can be one tone, but has enough info in sound to be able to distinguish between common trash and good signals). Has a couple of different coils, including DD coils that make it easier to seperate trash/iron from good targets. Also, has true all metal capability. I want a machine that I can use just my ears to do my discrimination with. In my experience discrimination just robs the machine of depth. I have a couple of ideas of what might fit this, but I really need some input.