Subwoofer Design with Moving Magnet Linear Motor

A new electro-dynamic transducer has been studied, based on a moving magnet linear motor instead of a traditional moving coil, and it has been carefully described into a recently presented paper from Claudio Lastrucci. This moving magnet motor could considerably improve the conversion efficiency and the sound quality at the lowest frequency range. It has been developed around a fully balanced and symmetrical moving magnet motor geometry and it can reduce the distortion, in the lowest range, to a fraction if compared to that of a conventional moving coil loudspeaker in the same range. It also offers a considerably higher power handling and overall robustness thus being able of reproducing the lowest range on bass spectrum with an unprecedented level of quality and output. The novel motor design also shows a considerable high acceleration that makes it suitable for the application also in the upper bass region. This paper proposes a review of the methodology that can be pursued in subwoofer design while using this motor technology. The new motor technology will require a different approach to subwoofer design. Several aspects that are in common with conventional loudspeakers will be outlined while also described those characteristics that differs significantly. The application of the technology and relative results will be shown through examples of practical applications and with measurement results. AES