Audio on cassettes can be distributed to smaller numbers of learners, and it has the benefit of allowing the learner control over when to listen.

Audio teleconferencing can connect groups of learners in real time, inexpensively and from any part of the world.There are several good reasons for using audio media:

• It can allow learners to hear ideas and opinions in the voices of experts and others who lend authority and authenticity (radio, audiotape, audio conference).
• It can allow learners to talk to experts and to other learners anywhere there is a telephone (audio conference).
• It can provide source material, such as a conversation, for the learner to analyze or react to (audiotape).
• It can talk the learner through a task, such as an experiment, when it would be disruptive to keep consulting written notes (audiotape).
• It can provide sounds of important past events or sounds from settings that learners cannot expect to visit (radio, audiotape).