According to this web site: "It appears that 900 MHz wireless speakers were first released by Recoton, which marketed them under three brand names: Advent, Acoustic Research and Jensen. But Recoton went bankrupt in April 2003. Thompson, the mother company of RCA, bought the division of accessories from Recoton, that included headphones and wireless speakers, and decided to continue their manufacture."
http://www.wireless-speakers.org/learn/wireless-speakers.html
