active noise attenuation kit or unit comprised of active electronic controllers, sensors, a speaker, power supply, and in the case of a unit, a structural interface module, said kit or unit for use in ducts, fans, transformers, vacuums, motors, mufflers, and headsets; active noise attenuation apparatus components, namely attenuation circuits, microphones and speakers for use in ducts, fans, transformers, vacuums, motors, mufflers and other industrial equipment