DD vs Concentric coils?

[tag1260]

What is the difference between a DD and a Concentric coil? And is there a specific purpose to each?
Thanks

[Stiffwrists]

I've always used a DD. Heres a few pictures.

[KOB]

Originally Posted by Stiffwrists View post
I've always used a DD. Heres a few pictures.

Very nice examples and pictures of coils. Thx

[MuddyMo]

I find the following to be true most of the time:
DD coils have more of a half football fov than a knife blade
DD coils separate better in one direction- when target to trash is is in a line from left to right
DD coils work better in high mineralization
CC coils go deeper but swings need to be overlapped by 1/3 of coil diameter
CC coils can separate deep targets better
CC coils ID more accurately- bottle caps etc
CC coils detect coins on edge better when swinging over the coins from edge to edge

[tag1260]

Thanks. It appears there are differences in when you would use each. Will either type work on a given MD if they're available?

[ghound]

I'd beg to differ on a few of these, in mild soil a cc can match a dd on depth, but not in mineralized soil.
A cc used to detect coins on edge better, but dd+higher freqs and multi freqs namely the Nox have balanced that.

Originally Posted by MuddyMo View post
I find the following to be true most of the time:
DD coils have more of a half football fov than a knife blade
DD coils separate better in one direction- when target to trash is is in a line from left to right
DD coils work better in high mineralization
CC coils go deeper but swings need to be overlapped by 1/3 of coil diameter
CC coils can separate deep targets better
CC coils ID more accurately- bottle caps etc
CC coils detect coins on edge better when swinging over the coins from edge to edge

[MuddyMo]

Originally Posted by ghound View post
.......
A cc used to detect coins on edge better, but dd+higher freqs and multi freqs namely the Nox have balanced that.

Not even the magical nox can make a DD as good as a CC at finding coins on edge in both directions. 3:00 into vid.
https://m.youtube.com/watch?v=ISiZGsp4OUo