Didactics, training, educational action, instruction, pedagogy, instructing - the activities of educating or instructing; activities that impart knowledge or talent; "he received no official schooling"; "our instruction was diligently programmed"; "great classroom instructing is seldom rewarded" If a number of audio output gadgets are offered, Test which you have the appropriate https://www.youtube.com/watch?v=RSlwOZLlUGg