Conventional bone conduction transducers, which are relatively large, suffer from poor performance at low frequencies. A new type of electro-dynamic transducer, the Balanced Electromagnetic Separation Transducer (BEST), was developed to improve the performance of the conventional transducers. The development was undertaken by Professor Bo Håkansson from Chalmers University of Technology.
By using a balanced suspension principle, the quadratic distortion forces, as well as the static forces between the vibrating parts, are principally counterbalanced. Both the distortion and the size of the transducer can therefore be considerably reduced. Moreover, the static and dynamic magnetic fluxes are separated, except in the air gap regions, giving a more efficient transducer.