Clean Earth Magnets Manufactured in Minnesota
Since 2020, Voice Coil and audioXpress magazines have tracked the development of the world's first high-performance, rare-earth-free permanent magnets, which are considered to be the biggest innovation in magnet technology in 40 years. Composed of abundant materials — Iron and Nitrogen — these magnets were developed from research at the University of Minnesota and are known commercially as Niron Magnetics’ Clean Earth Magnet technology. This breakthrough is a game-changer for the audio industry.
Niron's Clean Earth Magnets offer several advantages over NdFeB, AlNiCo, and Ferrite magnets. Unlike neodymium or cobalt, Niron's ingredients and processes are both abundant and highly scalable, with planned manufacturing in all regions, solving the current permanent magnet supply chain resilience challenges. Clean Earth Magnets are the most stable permanent magnet from -40°C to 160°C, virtually unchanged in both flux and coercive force over that range. They are also largely electrically non-conductive and thus resistant to eddy currents.
While processing costs dominate the manufacturing price of Clean Earth Magnets, the cost of raw materials — namely nitrogen and iron sources — are historically low and stable, supporting long-term pricing agreements. With a patented, scalable process, Niron has developed the first commercial mass production process for its proprietary Iron Nitride permanent magnets.
Neodymium (neo) replacement studies conducted by Menlo Scientific and Salvador Consultant on the generation 1 Clean Earth Magnets maintain the same topology as neo magnets, but with an aspect ratio more like AlNiCo, as the pot return structure is slightly deeper to accommodate the longer magnet slug. A less obvious implication of a deeper pot is higher excursion before the voice coil bottoms out. This impacts not only woofers, which can play louder, but also improves smartphone audio quality, allowing for a more natural voice sound due to extended response further down in the voice range.
