ALEXANDRIA, Va., June 4 -- United States Patent no. 12,323,777, issued on June 3, was assigned to GP Acoustics International Ltd. (Pak Shek Kok, Hong Kong).
"Loudspeaker circuitry" was invented by Sebastien Degraeve (Maidstone, Great Britain) and Jack Anthony Oclee-Brown (Staplehurst, Great Britain).
According to the abstract* released by the U.S. Patent & Trademark Office: "Electrical circuitry adapted to drive a dual-coil loudspeaker having a primary voice coil and a second voice coil connected in parallel with the primary voice coil, the second voice coil being in series with an LC resonant circuit of impedance Zmf, further comprising an inductance compensation filter of impedance Zif in parallel with the LC resonant circuit."
The pat...