Mari and I attended a Summer Solstice celebration at the Unity Church of Sarasota. It was held outside in the Unity Labyrinth. We have been told that Sarasota is one of 22 Crystal Cities of Light in the world. Here is a link to Jo Mooy article Prism of Light and Crystal City of Light.
The sound file you are hearing (if you have your sound on) was played and sung during the Solstice celebration and also sung around the world on the Solstice: The One Song Project. The chant is “OMA, KA, OM” pronounced “OM-AH, KA,OM”.