KNAC is a Los Angeles heavy metal FM radio station originally owned by Fred Sands that broadcast from January 8, 1986 at 105.5 MHz until February 15, 1995. However, KNAC was revived in 1998 as an internet based radio station.

In 1984, Fred Sands purchased the radio station at a bankruptcy auction.

Sands advertised in trade publications indicating his desire to hire a general manager with major market experience. Gary Price, an industry veteran, took the job and worked with Sands, who was intimately involved for the first year.

The antenna was moved from Signal Hill, California to Dominguez Hills, increasing the coverage area. In addition, Sands and Price ordered and installed state-of-the-art equipment for the new studio location and hired a new engineer.

With all the new improvements, Sands and Price recognized that KNAC needed a new sound as well. They selected a heavy metal format, targeting younger demographics. For the first time KNAC appeared in the Arbitron ratings and, once established, the station took in revenues of at least a million dollars per year. During the nine-year "Hard Rock" era, the KNAC program directors were Jimmy Christopher, Tom Marshall, Pam Edwards, Gregg Steele and Bryan Schock. Among the music directors at KNAC during that time frame were Ross Goza and Michael Davis. Davis' on-air moniker was "Jack The Ripper". Original on-air talent included Kat Snow as "Killer Kat," Lady Di, and Paul Lobster. Tawn Mastery took over Killer Kat's shift in 1986.

Bands in KNAC's playlist ranged from heavy metal, hard rock, classic rock and progressive rock such as Black Sabbath, Led Zeppelin, Iron Maiden, Judas Priest, AC/DC, Van Halen, Aerosmith, Kiss, Scorpions, Guns N' Roses and Rush, thrash metal such as Metallica, Megadeth, Slayer, Anthrax, Suicidal Tendencies and Testament, and grunge or alternative metal such as Faith No More, Alice in Chains, Soundgarden and Tool.

Sands and Price worked together for about ten years. Sands sold the radio station in 1994 for five times what he paid for it in 1984.

By early 1992, heavy metal was losing ground to the growing popularity of various "Alternative Subcultures". In trying to keep up with the times, KNAC began adding more music acts popular in the alternative music genre to its playlist rotation. The majority of these were the more guitar-based grunge acts like Pearl Jam and Nirvana as well as punk acts like The Offspring. While fans of the more adventurous and alternative earlier KNAC incarnation heralded a possible return to the previous format, many metal fans disliked KNAC's new sound, and the station, already in ratings trouble, saw further declines in audience shares. In 1994, management announced that KNAC was being sold and was switching to a Spanish-language music format. Heavy metal fans began tuning in again to find that KNAC had returned to its metal format for the few last months. Once again, headbangers could hear the classic metal they had not heard in a while, like Megadeth or Saxon.

Finally, the last day, February 15, 1995, arrived. James Hetfield and Lars Ulrich of Metallica appeared as guests to show their support. The last song to be played on KNAC was Metallica's "Fade to Black". At 1:59 p.m., KNAC went off the air with a short farewell message from general manager Gary Price.