a string of owners, purchased in 1986 by Sparkomatic, with the Pro equipment still made by Mark IV Audio, Mark IV sold out to Telex, who closed down the Pro division and folded its products into Electro-Voice. In 2005 Altec Lansing Technologies was acquired by Plantronics, 2009 bought by Prophet Equity, and has been owned since 2012 by the Infinity Group, a company which acquires struggling companies.

Popular loudspeakers included