An audio system includes an earplug with a speaker to deliver sound to the ear, and/or a microphone which captures sound in the ear canal, and an earmuff is worn over the earplug. The earplug receives sound signals from the earmuff (and/or transmits captured sound signals to the earmuff) by translating such sound signals into light signals which are transmitted over a free space situated between the earmuff and earplug. The light signals are then received at the earplug and/or earmuff and converted to electrical signals which may be further transmitted (e.g., from the earmuff to some external communications device) or converted to sound (e.g., in the earplug by having the electrical signals drive an earplug speaker). If power is required by the earplug, the need for on-board power sources may be avoided by converting light transmitted from the earmuff into power at the earplug. Electrical shock and physical snag hazards are avoided, and the earmuff is easily put on and removed, owing to the lack of wires or other physical connections between the earplug and earmuff. Additionally, by avoiding wires or radio transmission between the earplug and earmuff, electromagnetic interference may be reduced.