WNNX (100.5 FM, "Rock 100.5") is an Atlanta radio station airing a Mainstream Rock format. It is owned and operated by Cumulus Media. The station broadcasts from the same building as its other Cumulus Atlanta sister stations WWWQ ("Q100"), W255CJ 98.9 "99X", W250BC 97.9 "OG 97-9", WKHX 101.5 "Kicks 101-5", WYAY FM 106.7 "NewsRadio 106.7", and Dickey Broadcasting's WCNN "680 The Fan" and W229AG 93.7 in Sandy Springs near the Georgia Highway 400 and Interstate 285 interchange. WNNX's main transmitter is located in downtown Atlanta atop the Westin Peachtree Plaza Hotel.
- 1947 to 2001: WHMA-FM ("Alabama 100", country)
- 2001–08: WWWQ ("Q100", top 40 (CHR))
- 2008–present : WNNX ("Rock 100.5", mainstream rock 2008-2013/2014–Present / Active rock 2013-2014)
The 100.5 frequency has been in metro Atlanta, licensed to College Park, since early 2001. Before then, the station was licensed to Anniston, Alabama as WHMA-FM, broadcasting as country music station "Alabama 100". (After the move, that callsign shifted to another existing station in that area becoming WHMA-FM "The Big 95", 95.5 MHz)
Interested in moving the station to Atlanta, owner Robert Gammon proposed that it be re-licensed to Sandy Springs, and remain at 100,000 watts ERP (class C). An agreement had already been made with the nearest co-channel station, WSSL-FM in upstate South Carolina for it to move further away, however that station was sold to Clear Channel Communications in the interim and the agreement was negated. Additionally, the Federal Communications Commission (FCC) ruled that Sandy Springs was "not a community", citing its unincorporated status and letters of support from local organizations in Sandy Springs that had "Atlanta" as the address, as it laid out in unincorporated Fulton County at the time until Sandy Springs became an incorporated city in 2006.
After exhausting his funds in pursuit of the reallocation, Gammon sold the station to Susquehanna Radio. In a revised application before the FCC, Susquehanna proposed a different city of license, College Park. The FCC approved the application, mostly because the new application changed the class of the station from C (up to 100 kW at 600 meters or 1968 feet) down to C3 (up to 25 kW at 100 meters or 328 feet) to protect the licensed broadcast range of WSSL. Susquehanna was also forced to slightly null the station's signal in the direction of WSSL to stay in compliance with spacing rules. The move created spectrum space for two new radio stations in Alabama, but forced Southern Polytechnic State University low-power station WGHR and Georgia Public Broadcasting repeater W264AE (both 100.7 MHz FM) off the air in the Atlanta area. (Ironically, the 99X brand would later itself be moved to such a low-power repeater station.)
100.5's first format in Atlanta was top 40 station WWWQ ("Q100"), which made its debut on January 12, 2001, becoming the first mainstream Top 40 outlet in Atlanta for the first time since WAPW flipped to WNNX in October 1992 (though rival WSTR would shift between CHR and Hot AC for the better part of the 1990s). Despite its more limited signal, Q100 grew to the point that it often received higher Arbitron listenership ratings than several of its 100,000-watt competitors, including sister station 99X.
Susquehanna continued to pursue a larger signal for the station, eventually earning approval from the FCC to upgrade from class C3 to class C2. The upgrade occurred on October 24, 2005 at 5:00 PM, and is also when the station moved from the Turner tower to the Westin building.
In 2006, Cumulus acquired Susquehanna, including both 99X and Q100.
On January 11, 2008, Cumulus announced that Q100 would move to the 100,000-watt signal at 99.7 MHz. The transition began on January 21, when The Bert Show was simulcasted on both stations (as 99X's morning show was permanently cancelled the week before). 99X would sign off on 99.7 FM/HD1 and move to 99.7-HD2 at 5:30 AM on January 25. On the same day, after simulcasting until 6 AM, 100.5 began stunting, first with singer Beyoncé Knowles singing "To the Left" (from her song "Irreplaceable") and Bert Weiss redirecting listeners to the new frequency. At 10 AM, the stunting then switched to "Atlanta's Radio Idol", a loop where 8 different formats were presented. Listeners had the option to call the station and vote on which was their favorite. On Monday, January 28, 2008 at 5:45 AM, The Regular Guys announced the debut of "Rock 100.5", carrying a radio format similar to their previous station WKLS (formerly "96 Rock"), which itself changed formats to active rock as "Project 9-6-1". Rock 100.5's first song was "Baba O' Riley" by The Who. The two stations swapped callsigns on January 29.
In 2010, Rock 100.5 became the FM flagship station of the Atlanta Bravesfor that season through 2013 along with WCNN which continues carrying the team's games to this day, with NewsRadio 106.7 WYAY carrying the Braves games on FM since the 2014 season.
Throughout the station's existence, WNNX has shifted to different degrees of rock. From its sign-on until April 2009, the station aired a predominantly album-oriented rock format. At that time, the station leaned towards adult album alternative. In 2010, the station shifted back to its broad-based AOR format, which would last until late 2011, when the station shifted towards classic rock. Ratings for the station have been shaky, as the station usually ranks near a 2 share.
Merger with "98.9 The Bone"
On January 28, 2013, WNNX and sister station W255CJ ("98.9 The Bone") began promoting changes to the two stations on their Facebook and Twitter pages, promoting a "bigger and better change" to come starting February 1. The rumors stated the Cumulus Atlanta management were planning a possible merger of the two formats on one frequency, presumably on 100.5. These changes were confirmed two days later as the two stations merged on the 100.5 frequency. The official change took place on that Friday, February 1, at Midnight, when 98.9 and 100.5 began simulcasting. At 10 AM, the official relaunch took place, as WNNX shifted to active rock (the first song after the relaunch was "Chalk Outline" by Three Days Grace). The simulcast lasted until February 4 at Noon, when 98.9 flipped to a new format, Christian country, under the name "The Walk." 
"Atlanta's Classic Rock"
After broadcasting an active rock format for barely a year, the station flipped formats once again and began broadcasting classic rock on January 3, 2014, competing with rival station WSRV ("97.1 The River"). The station's playlist is now similar to what it was in 2012, prior to its shift to active rock.
"Atlanta's Rock Station"
The station's current iteration began in mid-2016 with a slogan tweak to "Atlanta's Rock Station." No personnel changes were made and the music was slightly updated to move into the 90s and begin featuring music from the grunge era of rock.
Bailey & Southside
Rock 100.5's morning show is "Bailey & Southside", featuring main co-hosts Jason Bailey and "Southside" Steve Rickman with Brandi Britain and "Digidude" Nate Hanson. Bailey came to Rock 100.5 in 2015 after one year stints each at WZGC/Atlanta (92.9 The Game) and Sirius XM where he used the name "Buckethead", an airname he also used for 8 years at WTKS-FM/Real Radio 104.1 in Orlando, Florida from 2008 to 2013. Rickman was formerly a member of "The Regular Guys" which was the station's morning show until their final breakup in 2015.
The Regular Guys had two successful runs at cross-town rival and Clear Channel owned 96 Rock before being fired twice. The first firing happened in 2004 when they accidentally aired explicit audio of a discussion with pornographic film actress Devin Lane over a commercial. That audio was intended be played backwards in a bit called "backwards smut" when they returned from the break, mocking the FCC indecency crackdown at the time stemming from the Super Bowl XXXVIII halftime show controversy. Larry Wachs and Eric Von Haessler were rehired by Clear Channel at sister station news-talk WGST in March, 2005, before moving back to 96Rock for a second stint starting that summer, but were fired again in 2006 for secretly taping co-workers' conversation in the restroom. The co-workers were 2 DJs from a sister station who tried to sue Wachs over the recording and its broadcast but the case was later dropped for having no merit.
Regular weekly staff
- Lyndsey Marie Cooke. Became the official midday replacement on June 1, 2011. She is from Florida, by way of Michigan, and used to work at K-Rock 96.1 in Ft. Myers, Florida.
- Jay Philpott. Has hosted afternoon drive since April 2015. He has previously worked at rock stations in Baltimore, St. Louis, Milwaukee, Dallas, Seattle and Minneapolis. Philpott is also the station's Assistant Program Director, working with PD Greg Ausham.
- Axel Lowe. Hosts the evening time slot. He was previously on Rock 100.5 inn afternoons from the station's launch in 2008 through 2010. He started at sister-station at 99X/The Bone and returned to the station for a second stint to do the morning show (and later, middays) before its merger with Rock 100.5.
- Tommy McNulty. Works weekend shifts on the station. He previously worked on 99X/The Bone before returning to do weekends. Tommy is also a local Atlanta musician.
- Dave Clapper. Works weekends and fill-ins. Clapper was previously the Program Director of 97.1 The River before joining WNNX in the summer of 2016.
- Jackson. Hosts weekends and serves as the station's Public Affairs Director.