Patent ID: 6934402
Filing Date: 2005-08-23
Classification: H04R

Abstract:
1. A planar-magnetic transducer comprising: at least one thin film vibratable diaphragm with a first surface side and a second surface side, including a predetermined active region, said predetermined active region including a predetermined conductive surface area for converting an input electrical signal into a corresponding acoustic output; primary magnetic structure including at least three elongated magnets placed adjacent and substantially parallel to each other, said magnetic structure configured to cooperate with the conductive surface area conducting an electrical signal to actuate the active region to produce an acoustic output; a mounting support structure coupled to the primary magnetic structure and the diaphragm to capture the diaphragm, hold it in a predetermined state of tension and space it at predetermined distancing the primary magnetic structure adjacent one of the surface sides of the diaphragm; said conductive surface area including elongate conductive paths running substantially in parallel with said magnets; the mounting support structure, the at least three magnets of the primary magnetic structure, and the diaphragm having coordinated compositions and being cooperatively configured and positioned in predetermined spaced apart relationships wherein (i) the mounting support structure stabilizes the diaphragm in a static configuration at the predetermined tension which remains stable over and between extended periods of use, despite occurrence of dynamic conditions in response to extreme high energy forces driving the diaphragm to audio output, and (ii) the high energy magnetic forces interacting between the at least three magnets do not interfere with the predetermined tension of the diaphragm; at least one secondary magnet structure positioned adjacent to the opposite surface of said thin film diaphragm from the primary magnet structure and spaced a predetermined distance from said diaphragm; said secondary magnet structure being directly adjacent less diaphragm surface area than said primary magnet structure, said transducer being configured so that the secondary support structure has a more open architecture and significantly more open space than the primary support structure, allowing passage of acoustic energy with significantly less interference from the secondary support structure than the primary support structure and wherein a plurality of elongated magnets of the primary magnetic structure are without corresponding magnets of opposing position in the secondary magnetic structure, the transducer thereby configured to have an essentially single-ended configuration over a portion of the diaphragm; said planar-magnetic transducer being operable as an enhanced single ended transducer.