HOWARD COGAN is "Jack," the voice of a new radio format that has sprouted all over the country in the last year with an iPod-like shuffle of songs, the occasional snarky voice-over and not much else.
Mr. Cogan has also been "Bob," Jack's biggest competitor.
In short, he is the real person behind some of the nonpersonalities that have replaced real personalities to address radio's personality crisis.
Suddenly radio is awash in monosyllabic new personae - not just Jack and Bob, but also Dave, Hank, Ben and Max, most of whom are heard in a cycle of prerecorded snippets all day and night between blocks of music.
Created in Canada and exported to the United States only 15 months ago, Jack is by far the most widespread new nonperson in the bunch, heard on 18 stations here. But competitors and imitators are proliferating. Right behind with about 10 stations is Bob, followed by a ragtag bunch of Dougs, Mikes, Simons and Hanks. (There is a woman, Alice, but that's the name of a more standard alternative format.)
The pseudopersonalities may vary, but they're all part of an effort to introduce variety, boost ratings and cut costs. The stations that use these formats play hit songs from the last three decades, sometimes four or five times as many songs as on most commercial stations. The formats also give stations an identity when real radio personalities are given the ax - as happened most prominently to Cousin Brucie, a k a Bruce Morrow, of the oldies station WCBS-FM in New York, which got Jacked just last month.
Mr. Cogan and others like him are skilled voice-over actors who, while a nearly constant presence on the stations, have no connection to the music: the songs are chosen by the station's program directors, with some help from outside consultants, as has been the usual practice for decades. Thanks to corporate consolidation and shortened playlists, the influence of disc jockeys on what songs get played on the radio was weak even before the advent of Jack and his brothers.
But program directors and analysts say the voice-over identities are better than D.J.'s at making stations memorable to listeners when they fill out quarterly audience surveys.
And though the Jack figures may not be real people, they do have personalities - sort of. "If we do our jobs well," said Rob Barnett, the president of programming for Infinity Broadcasting, which has nine Jack stations, "then Jack is a persona that is dedicated to having fun, both at the sometimes uptight nature of radio programming, and having fun with popular culture."
At WCBS, Jack is a voice of sarcasm and ennui, mostly untouched by current events; he does not identify songs, read news or give traffic or weather reports. In a self-deprecating shrug of a tone, he plugs the station constantly ("It's like an iPod, only the batteries never run out") and now and then spouts a politically incorrect remark ("Maybe if you stopped saying 'I don't speak English,' you'd understand me").
Bob, whose stations favor more current music, is even milder, seeming almost polite as he refers to himself, as Jack does, in the third person. ("If you think there's something he should play, send us a note. If he likes it, Bob'll play it.")
When a new Jack or Bob or Mike station enters a market, there tends to be a spike in ratings. But according to a new study by the ratings service Arbitron and Edison Media Research, Jack and Bob face two problematic trends. At many such stations the audience size has diminished as the novelty of the format wears off, and the time each person spends listening to the station - an important statistic for advertisers - is fairly low, suggesting that people tune in for the fun of the songs but tune out in a short time for what other stations offer: on-air personalities and local news, perhaps.
"What you end up with is a lifeless station," said Robert Unmacht, a consultant at iN3 Partners in Nashville.
The D.J. firings have drawn criticism from the American Federation of Television and Radio Artists, which represents announcers. And at WCBS in New York, the abrupt format switch brought street protests and appeals from Mayor Michael R. Bloomberg and Senator Charles E. Schumer. Many Jack and Bob stations that began broadcasting without D.J.'s have gradually phased them back in after several months, and Mr. Barnett, the Infinity programmer, said he might introduce "some form of personality" to Jack stations as they mature.
Still, the almost-anything-goes eclecticism of the format, sometimes called adult hits, seems to appeal to listeners accustomed to scanning through thousands of MP3's at a time. "Variety has now become a niche," said Howard Kroeger, a programmer in Winnipeg, Manitoba, who helped create the Bob format in 2002 after he went to a 40th-birthday party and found that his crowd had tired of the narrower classic-rock format. They wanted newer songs - late-70's one-hit-wonders, stars from the early MTV era - and they wanted a broad selection of them.
Radical juxtapositions of sounds, like Twisted Sister following Barry White and Van Halen going straight into the O'Jays - segues once abhorred in the radio business as "train wrecks" - are now deliberately cultivated by programmers drawing from decades of Top 40 lists.
Mr. Cogan, 40, the voice of Jack, is based in Toronto and has been with the Jack franchise since it was begun in Vancouver in 2002. A voice-over actor for Canadian television and radio ads, he developed the Jack manner using the "undersell" approach of TV commercials, the opposite of the usual stentorian bombast of radio. "I said, maybe we should try this on radio," he said, "as opposed to where everybody is doing the oversell, dramatic 'voice of God' all the time."
Mr. Cogan described Jack's attitude as "a little indifferent and even." He added: "He doesn't get too excited. He's unaffected by life."
Jack and Bob's imitators include Ben, in Philadelphia (WBEN-FM), which aims to attract women by playing plenty of Cyndi Lauper and Matchbox 20; Hank, in Indianapolis (WENS-FM), which applies the Bob format to country (C. W. McCall to Mary Chapin Carpenter); and others whose personalities are more difficult to discern, like Max in San Francisco, Mike in Boston and Simon in Greensboro, N.C.
Two months ago SparkNet, which licenses Jack to stations in the United States and Canada, filed a lawsuit against Bonneville, a station owner, alleging trademark infringement: SparkNet says Jack's slogan, "Playing what we want," was cannibalized into "Whatever we want" and similar phrases on four of Bonneville's stations. A hearing is scheduled for next week in Chicago.
Mr. Barnett and other Jack proponents say the format is a malleable enough to be adapted to the tastes of any city, leading to regional variations: New York's Jack fits in more hip-hop, for example, playing songs like Digital Underground's "Humpty Dance" that don't turn up often on other Jacks.
Each station writes many of its own Jackisms, which led to an odd political showdown last month between Jack and Mayor Bloomberg after The New York Post reported that the mayor, a fan of WCBS and Cousin Brucie, said, with an expletive, that he would never listen to the station again. By noon that day, Jack had responded: "Hey, Mayor Bloomberg. I heard you took a shot at us in The Post. What's with all the swearin' like a sailor? Fleet week is over. It's just music."
So far, the mayor has declined to reply.