All Metal vs. Discrimination Modes
You will get more depth while in all metal mode.
I cannot speak to all the different manufactures brands and how they design their detectors. However, the all metal mode is a raw signal that is going through one channel, while discrimination mode is going through two channels and gets analyzed or compared by phase shift of the two channels. Using phase shift technology will introduce a loss of depth. Discrimination adds other circuitry like filtering and digital signal processing (DSP) to the equation. Filtering will reduce overall depth. Having a deeper detecting detector will also present issues with target identification. A “True” all metal mode literally uses a “raw” unfiltered signal.
You can have your detector in discrimination mode and set it to not reject any targets. You will accept all targets and be using “zero discrimination”. All targets will respond. However, you are not in a true “All Metal Mode”. You are still using discrimination filtering circuitry and still not detecting in a “True” all metal mode. A true all metal mode utilizes no DSP or filtering circuitry. It is a raw signal that bypasses the filtering stage(s) and you will immediately get an audio response. Understand that depending on manufacture and metal detector design that some detector manufactures machines are not true all metal mode detectors. They will designate zero discrimination as “all metal”. This zero discrimination mode still incorporates filtering circuitry.
Now, knowing this, in most cases a metal detector in “true “ all metal mode (no filtering) will detect deeper than when using discrimination.
