The moving coil audio transducer as we know it was invented by Rice-Kellogg in 1924. Notice that in more than 100 years, the asymmetric topology appears remarkedly similar to audio transducers of today.
Is that the GENELEC coaxial's patented flat surround et al?
Note that the digital audio transducer still seems father away than Mars, even though IBM and Bell Labs tried and failed to develop one in the 1960's.
I found three (3) expired US Patents that claim the Commutated Voice Coil as an invention.
1. US8284982 Positionally sequenced loudspeaker system by Adam H. Bailey, filed 6 March 2007, status: Expired - Fee Related
2. US5748753 High power audio subwoofer by Robert W. Carver, filed 2 January 1996, status: Expired - Fee Related
3. US4531025 Loudspeaker with commutated coil drive by Thomas J. Danley and Charles A. Rey, filed 19 March 1984. status: Expired - Lifetime
I was unable to identify any active commutated voice coil US Patents.
Having said that, I thought I would turn to the ASR community for a discussion on why the loudspeaker industry has failed to make progress on the development of the digit transducer or to even implement any commercial products containing transducers with commutated voice coils regardless of claims of invention.
Is that the GENELEC coaxial's patented flat surround et al?
Note that the digital audio transducer still seems father away than Mars, even though IBM and Bell Labs tried and failed to develop one in the 1960's.
I found three (3) expired US Patents that claim the Commutated Voice Coil as an invention.
1. US8284982 Positionally sequenced loudspeaker system by Adam H. Bailey, filed 6 March 2007, status: Expired - Fee Related
2. US5748753 High power audio subwoofer by Robert W. Carver, filed 2 January 1996, status: Expired - Fee Related
3. US4531025 Loudspeaker with commutated coil drive by Thomas J. Danley and Charles A. Rey, filed 19 March 1984. status: Expired - Lifetime
I was unable to identify any active commutated voice coil US Patents.
Having said that, I thought I would turn to the ASR community for a discussion on why the loudspeaker industry has failed to make progress on the development of the digit transducer or to even implement any commercial products containing transducers with commutated voice coils regardless of claims of invention.
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