Polymaker Edition

FD51-4PM, using Polymaker Polywood to create a higher efficiency FD51 driver

FD51-4PM is another version of FD51 released for you to make at home. FD51-4PM utilises then benefits of Polymakers filaments to enable a higher sensitivity driver compared to FD51-4PM. This difference is by as much as 2-3dB. This is thanks to the tighter tolerances and the lightweight properties of Polywood. This low density material reduces the moving mass by 0.4g which doesn’t sound like much, but this is enough to enable over twice as long playback on battery power at the same sound levels as FD51-4OS.

FD51-4PM is released under the Creative Commons – Attribution – Non Commercial license. Polymaker have supplied the materials during development to make this driver possible.


FD51-4PM is also a great educational tool for anyone learning or interested in acoustics. The design has been made compatible with Thomas Sanladerer’s M3-SK experimentation kit, allowing you to change up your driver and cabinet.


What do I need to make FD51-4PM?

  • Polywood (For Cone & Former)
  • Polyflex TPU 95A (For Surround & Spider)
  • PolyMax PLA / Polysmooth / Polywood (For Chassis & Cabinet)
  • 2x (15x10mm) N35 Neodymium Magnets (Per Driver)
  • 37SWG Wire (0.17mm) or 33AWG (0.18mm) copper wire
  • M5 Washers (15mm Diameter maximum)
  • Contact Adhesive Glue

FD51-4PM adds only washers as a component compared to FD51-4OS. This change is due to extracting more power from the magnet motor design, which is helped from the Polymaker filaments. Most of the advantage is from the Polywood material reducing moving mass.

Download files will be made available here once prototyping is complete

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