Acoustic transducers, namely, electroacoustic transducers and acoustoelectric transducers; rotational action electroacoustic transducers; rotational action acoustoelectric transducers; sound reproduction devices and systems, namely, loudspeakers, headphones, earphones, headsets for telephones, headsets for mobile or cellular phones, headsets for computers, tweeters, subwoofers, mid-range drivers, wireless speakers, speakers for cellular or mobile phones, speakers for computing devices and spe...