Metal Detector Coils Explained
DD vs Concentric vs Mono
Understanding search coils is essential for getting the most from your detector. Learn about DD, concentric, and monoloop coils.
- 1Coil Types
- 2Size Considerations
- 3Specialized Coils
- 4Choosing the Right Coil
DD (Double-D) Coils: - Two overlapping D-shaped windings - Best ground coverage per sweep - Better stability in mineralization - Standard on most modern detectors
Concentric Coils: - Inner and outer circular windings - Cone-shaped detection field - More precise pinpointing - Can struggle in bad ground
Monoloop Coils: - Single winding - Used mainly on PI detectors - Maximum depth - Wide detection field
Small Coils (5-8"): - Better target separation - Works in tight spaces - Faster sweep speed - Less depth
Medium Coils (9-11"): - Best all-around size - Good depth and coverage - Standard equipment on most detectors
Large Coils (12"+): - Maximum depth - More ground coverage - Heavier and slower - Best for open fields
Elliptical Coils: - Easier to maneuver - Good for trashy areas - Popular mid-size option
Spider/Open Coils: - Reduced weight - Works through vegetation - Some depth sacrifice
Imaging Coils: - Multiple winding array - Better target separation - Premium option for top detectors
Match Coil to Conditions: - Parks with trash: Small DD - Open fields: Large DD - Beach water hunting: Medium DD - Tight between rocks: Small concentric
Upgrade Considerations: - Stock coils are usually good - Large coil = more depth - Small coil = more separation - Aftermarket options expand capabilities
Care: - Use coil covers always - Check connection periodically - Store flat or hanging - Avoid extreme temperatures
Detectors We'd Recommend After Reading This
Our current picks for the kind of hunting this guide covers, ranked on rating and review volume.
Garrett ACE 300
Garrett's ACE 300 bridges the gap between toy detectors and serious machines with 0-99 Digital Target ID for accurate identification. Five preset search modes eliminate guesswork for new hunters, while the 7x10" DD coil provides solid depth. Made in USA with Garrett's proven reliability at an accessible price point.
Price may vary
Garrett ACE 400
The ACE 400 hits the sweet spot in Garrett's lineup with a 0-99 Digital Target ID scale and adjustable frequency that helps reduce interference. Iron Audio lets you hear masked iron targets, preventing false digs. The included 8.5x11" DD coil covers ground efficiently while the USA-made build quality ensures years of reliable use.
Price may vary
Nokta Simplex Ultra
The Simplex Ultra upgrades the beloved Simplex+ with simultaneous multi-frequency and more single-frequency options. Still maintains the original's simplicity and IP68 waterproofing while adding serious capability. The rechargeable battery and included wireless headphones make it hunt-ready out of the box.
Price may vary
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