A Silent Disco is typically the same as a normal disco except the dancers wear headphones. These headphones use wireless technology to connect to a transmitter. The transmitter sends the music to all the headphones simultaneously so everyone can dance but nobody without headphones can hear anything. Weird, right? However, one advantage is that several transmitters on different channels can each transmit different playlists of music (eg 60s, 70s and modern) and each headphone wearer can select their preferred channel. So you can listen to completely different music to your friends in the same place at the same time.
We use this technology slightly differently. When we dance on the beach, each participant received a pair of headphones tuned to the same channel as the transmitter. The carefully designed Earthdance routine playlist is then played to all headphones, including the instructor. The instructor has a head mic which enables her to talk to everyone at once and describe the moves. The headphones have a volume control so you can adjust the volume to a level to suit yourself.
This means that we can dance anywhere without disturbing anyone else and without anyone else disturbing us! You will be totally immersed in the music with no distractions.