Audio equipment transmits, receives, and reproduces audio signals to communicate between locations over a distance. Two-way radios and accessories are real-time communication tools that allow people to share information and alerts, collaborate, and coordinate action. Portable radios tune into AM, FM, and shortwave frequencies to play music and broadcast news and reports. Phones and accessories connect with landline phone services to make and receive calls. Marine stereo systems include parts, components, and speakers to build radios for use on boats, ships, or near marinas. Headphones and headsets allow hands-free communication in loud and noisy industrial and commercial areas. Digital voice recorders store and replay voice recordings. Speakers and public address equipment broadcast music, announcements, and alarms over a large area. Intercoms provide audio and video communications between two points in a facility.