Patent ID: 8761433
Filing Date: 2014-06-24
Classification: H04R

Abstract:
1. A variable-impedance electro acoustic transducer comprising: a coil former spaced within an air gap formed between a first magnet and at least a second magnet, the coil former around which at least three coils are wound, the first magnet being disposed between a top pole and a bottom pole plate directly coupled to the at least second magnet; and a single switch in communication with a first coil and a second coil such that when the single switch is in a first position the transducer has first net impedance value, and when the single switch is in a second position the transducer has a second net impedance value; where when the single switch is in the first position, the first coil is in series with the second coil to form a series combination in parallel with a third coil, and when the single switch is in the second position, the first coil is in parallel with both the second coil and the third coil.