Two box systems definately go deep,some times too deep.example. Larry Wilson was detecting pattons camps and came up with a horrendous signal-eureka I'm gonna be rich!!!!Twenty two feet and many weeks later he was the proud owner of a model t spoke wheel rim. When going deep computer enhanced side scanning sonar paints gold-gold-outline pocket and shows where to dig-gotta love it but darn expensive. Don't know of any two box with disc. to wipe out junk signals,lotza luck,hope you love to dig!!! Hoser John