KESP gained its current call sign, and format, in the early 2000s. Other call signs used since it came on the air in 1951 were: KBOX (1951–1956), KBEE (1956–1983), KHYV (1983–1988), KOOK (1988–1992(?)/1996(?)),[3]KBUL (1996–1998), and KANM (1998–2000).[3]
The station was owned by the McClatchy family, which also owned McClatchy Newspapers, publisher of the Modesto Bee. (The McClatchy Company has since sold the station to Citadel Broadcasting, which merged with Cumulus Media on September 16, 2011.[4])