3″ Subwoofer Voice Coil Shim Adapter

3″ Subwoofer Voice Coil Shim Adapter

Get factory-level coil alignment with our 3″ subwoofer voice coil shim adapter, trusted by professional speaker manufacturers and serious audio builders. This precision-cut tool makes subwoofer recones faster, easier, and more accurate than using paper or plastic strips. It eliminates misalignment and reduces the risk of coil rub, voice coil gap damage, and recone failure caused by poor centering during installation.

Our voice coil shim adapter is designed for voice coils with a 3″ (76.2mm) inner diameter and motors with a 2.94″ (74.6mm) outer diameter pole piece. The snug fit keeps the coil perfectly centered in the magnetic gap. As a result, spacing remains consistent throughout the glue-up and curing process. This leads to smoother movement, better long-term durability, and fewer build issues—regardless of the project scale.

In addition, we use a high-strength composite with a smooth, non-stick surface. It won’t warp, compress, or bond to adhesives. Because it holds shape under pressure, it performs reliably across repeated recones. The rigid design makes it easy to install and remove, even in tight or awkward builds. Compared to makeshift alternatives, it delivers repeatable, professional-grade results with less effort and more confidence.

We recommend using this shim for voice coil formers up to 5.5″ tall. It also works with taller coils, though removal may require extra effort. This is normal and doesn’t affect performance. Most importantly, the shim is reusable and retains its shape across multiple builds without losing precision.

Ideal for recone kits, speaker repair shops, subwoofer builders, mobile audio techs, and home audio restoration.

Upgrade your recone process with the tool trusted by professionals worldwide—for cleaner installs and consistent results, every single time.

Designed to fit the Lord of Bass UA3 motor and any motor platform with a 3.842″ pole outer diameter.