All sound speakers have a permanent magnet located behind the center of cone, no matter what size or how powerful the speaker is, to produce the sound by interacting with the changing magnetic field, driving the cone. Speaker manufacturers have been searching a long time for better magnet in speaker driver to achieve the best of tone quality in different ranges, such as AlNiCo, Ferrite, Neodymium, SmCo etc. HRS Magnet can provide speaker magnet based on your design.