Equipment and apparatus for self-administering a hearing test; equipment and apparatus for processing of sound; equipment and apparatus for filtering sound and soundproofing; sound-filters; sound transmitting apparatus; sound bars; loudspeakers; equipment and apparatus for amplifying sound; equipment and apparatus for modifying audio signals; wireless headsets for smartphones; earphones and headphones; headsets; ear buds; earphone accessories, namely, earphone cushions, earphone pads, cord management systems, earphone cases, and earphone extension cords; data processing apparatus; software related to these apparatus, devices and equipment