Ultimate Ears is an American custom in-ear monitor (IEM), speaker, and earphone manufacturer based in Irvine and Newark, California, United States. The custom in-ear monitor company was founded by Mindy and Jerry Harvey in 1995 and it created a new market for custom IEMs which are now used by most of the world's top musicians. In August 2008, Ultimate Ears was acquired by Logitech and operates as a subsidiary.