The oldest of the stations is the one licensed to Arcadia, California, which signed on in 1960 with original callsign KMAX. It was owned by Max H. Isoard and his Sierra Madre Broadcasting Company; it aired a format targeted at various ethnic groups. In 1988, John Douglas bought KMAX with the intent to integrate it with other stations that would serve the entire Greater Los Angeles area with a rimshot signal. He accomplished this by purchasing two stations in San Diego and Ventura counties that had been operating separately, middle-of-the-road outlet KAVO in Fallbrook and adult contemporary-formatted KAGR in Ventura, for $2.1 million. Together, these three class A FM stations broadcast a city-grade signal across Los Angeles County and surrounding counties, at a lower cost than purchasing a single class B station. Initially, the trimulcast retained its format of brokered-time programming, much of which was targeted to the African-American church community. One popular show during this time was Spiritual Vibes, a gospel music show hosted by Ollie Collins, Jr. Also in the lineup was an all-night program playing classic, traditional, and contemporary "black gospel" music, hosted by veteran gospel music DJ "Sister Ruth" Dixon, known for her signature Caribbean accent. In 1994, the trimulcast switched to a sports format under the "Sportsmax 107.1 FM" name and call letters KMAX, KBAX, and KAXX. Sportsmax hosts included Joe McDonnell, the SportsGods, and Rich Herrera. The stations broadcast games featuring the San Francisco 49ers, Oakland Raiders, Notre Dame Fighting Irish football, and the Los Angeles Ice Dogs of the International Hockey League. Additionally, the triplecast aired urban talk/R&B program The Tom Joyner Morning Show weekdays for a brief time. In November 1995, Douglas sold the three stations, along with co-owned KWIZ-FM in Santa Ana, to Odyssey Communications for $35 million. The following year, on March 27, 1996 at 4 p.m., Odyssey flipped the trimulcast to a modern rock format branded "Y107", with the stations' respective call signs changed to KLYY, KSYY, and KVYY. Y107 competed directly with Los Angeles' established alternative rock station, KROQ-FM.
Spanish formats
On December 13, 1999, the trimulcast stations flipped to Spanish adult contemporary as "Viva 107", retaining the same call signs. On December 24, 2002, following owner Big City Radio's Chapter 11 bankruptcy filing, Entravision Communications purchased KLYY, KSYY, and KVYY for $137 million in cash and stock. Viva remained on air for a short time following the sale. In 2003, the 107.1 FM trimulcast adopted a rock en español format branded "Súper Estrella". The format originally launched in 1997 on KVAR in Riverside, then expanded to KACD-FM in 2000. Accompanying the flip was a set of new call signs to match: KSSE, KSSD, and KSSC — the first of these moving from the Riverside station. On July 13, 2007, KSSE started adding three to four English-language songs per hour. The first song in English was "Move Ya Body" by Nina Sky at 9:04 p.m. On January 5, 2015, the KSSE/KSSD/KSSC trio was among the first Entravision-owned stations to launch El Show de Piolín, a nationally syndicated program hosted veteran radio personality Eddie "Piolín" Sotelo. On December 1, 2016, after Entravision's other Súper Estrella stations had slowly disappeared across the United States, all air staff was let go and KSSE's trimulcast began stunting. The last song played on Súper Estrella was "Persiana Americana" by Soda Stereo. On December 5 at 12:02 a.m., the station flipped to Spanish oldies under the name "La Suavecita". Súper Estrella became an online-only service with four distinct streams.
José and end of the trimulcast
On January 7, 2019, Entravision broke the 107.1 FM trimulcast. KSSE and KSSD dropped La Suavecita and began simulcasting KLYY and its Spanish adult hits format; this new trimulcast is branded as "José 97.5 y 107.1". KSSC in Ventura County retained the "La Suavecita 107.1" branding until December 31st. KSSC is currently branded as "José".
