ALEXANDRIA, Va., Oct. 8 -- United States Patent no. 12,439,209, issued on Oct. 7, was assigned to Sound Solutions International (Zhenjiang) Co. Ltd. (Zhenjiang, China).

"Speaker with improved frequency response and related electronic sound signal circuit, sound system and production method" was invented by Hong-Bi Dong Nguyen (Vienna) and Friedrich Reining (Vienna).

According to the abstract* released by the U.S. Patent & Trademark Office: "The invention relates to a speaker (1) comprising a coil arrangement (2) with at least two voice coils (3a, 3b), a magnet system (4) and a membrane (10) being fixed to the coil arrangement (2) and the magnet system (4). The membrane (10) has a first compliance (c1) and together with the coil arrangemen...