KXLL, "Excellent Radio," is the third of the KTOO triumvirate. It's trying to target the 18-to-30-year-old demographic. So far, the strategy has been a randomized 5,000-plus song stream that jumps from Top 40 to rock to hip-hop to 1960s classic to punk. It's not unlikely to hear The Shins followed by Jefferson Airplane followed by The Verve.

"I've always been one of those dork guys who gave girlfriends mix tapes," Kline said. "This is the mix tape for Juneau. It's a mix tape for 30,000 people.

"That's one of the reasons why I feel we have to step outside the bounds of what would be considered adult contemporary, Top 40 music. Hopefully people will tune in to the station to hear something they've never heard before."

How do you define a demographic through music? How can you build programming around age, when tastes are so subjective?

"Music is art, and you can't sit two people in front of a Matisse and say, 'OK, scientifically describe why you like this Matisse,'" Kline said.

"I want to run a Top 40 station that young people can listen to and feel like it's the type of music that makes them feel connected to what's going on," he said. "But I also want them to have some understanding of the roots and breadth of popular music."

Four thousand songs - bought from the independent Colorado-based programmer Jones Radio Networks and shipped on a single, palm-sized, 100-gigabyte hard drive - make up the core of the KXLL library.

Jones sends the station two more CDs a week with the latest country, adult contemporary, rock and urban singles, and Kline picks the songs he wants to add.

Beyond that, he's added about 500 more songs - CD and vinyl - from the KTOO library.

This weekend he burned the second track, "+81," from Deerhoof's brand-new "Friend Opportunity" release. Days earlier, he added "A Town Called Malice," by the Jam and at least 10 Stevie Wonder songs.

"We had three Stevie Wonder songs, and one of them was 'Part-Time Lover,'" Kline said. "I had to get more Stevie Wonder. There's stuff that needs to be in there. That's going to be a multiple-year project."

The songs in the library are assigned a genre: "Rock New," "Pop New," "DJ Electronica" and "Punk," for instance, or "Hot List," for the 50 to 100 new songs that Kline chooses to feature.

Kline uses his scheduling database to map the structure of each hour of programming. Right now, every hour starts with a "Hot List," then proceeds through "Pop New," "Pop 90s," "Pop New," "60s/70s," "Pop New," "Punk" and "Hot List" for the first half-hour.

The software randomly selects a song from each genre to fill each hour. Since "Hot List" contains just 50 to 100 songs, those songs end up playing more often.

An astute listener can listen to two songs and determine the time.

"If soul is playing, I can tell you it's 10 minutes before the end of an hour," Kline said. "If punk is playing, I can say it's 25 past."

That basic structure will likely change in the future, depending on the time of the day. There could be more rock and soul in the evening, for instance.

Kline fine-tuned the fundamental structure during the two-week experimental broadcast between KTOO's purchase of the STAR and MAGIC transmitters (Dec. 27) and the actual grand-launch (Jan. 13).

He discovered that the "Dance/Hip-Hop" category, mostly feel-good music from the 1970s and 1980s, wasn't meshing well. One K.C. and the Sunshine Band song would lend an entire hour a goofy, novelty feel. A similar phenomenon was happening within the rock category.

"A lot of the stuff that was coming out in the late 1990s is Metallica-influenced, really heavy guitar stuff," Kline said. "A lot of that stuff I really love, but in the pop mode, it really dragged it down somehow. We want to keep this a fun station.

"I've decided that for a while I need to go with what I like and let people give us feedback and try to respond to it in some measured way," he said. "If I responded to what everyone said all the time, I'd go crazy."

Not that the station isn't already consuming him. Kline listens obsessively, waking up at 5:30 a.m. some days and tuning in on the clock radio. Ultimately, he had to learn to accept that the mixes and the segues wouldn't be perfect, but the songs would be ones he liked.

Kline grew up in Boston listening to WBCN, a Top 40 station credited with discovering Aerosmith, The J. Geils Band and The Cars, among others. In high school, he moved with his family to Fort Myers, Fla., where he once shadowed a DJ at Super Q 96.

"It was this awful station, but watching a DJ, I was totally enthralled," Kline said.

The University of Florida's college station was a mediocre Top 40 outlet. But Kline and a few friends set up a pirate radio station, Buzz 93, in the basement of their dorm. It reached to the fifth floor.

Kline eventually moved to Juneau in 1991 to be the "Morning Edition" anchor for KTOO. He did that for less than a year before he was working with the state.

He spent 12 years in various state capacities: with the Department of Fish and Game, the governor's office, the Department of Administration and as the webmaster for the state's Web site. For the last three years, he's worked for CGI, a software company that has contracts with the state.

That entire 12 years, he hosted a KTOO volunteer show, "Midnight Capers," at midnight on Saturdays.

"My dream station would be a college rock station, but I don't think it's realistic to think we're going to have a college rock station that's going to be a great service to Juneau," Kline said. "There's no Top 40 station, and I think a Top 40 station that mixes it up a little bit is valid.

"(This is) a dream job, because they've provided me with absolute freedom to do what I think is going to work based on a lot of experience I've had with doing volunteer radio shows and just musical taste," he said. "They trust the fact that I respond to people, and that I'm not going to go off on a tangent and do something that no one likes."

So far, the biggest complaint has been the segues. New wave to soul is jarring for some. Others don't mind. Tastes vary, and the transitions on KXLL reflect Kline's desire to show the parallel influences in musical styles.

The genre-bending is best illustrated with the popular "mash-ups" that currently dominate the Hot List. They're essentially two or more seemingly disparate songs that somehow meld through a combination of beat- and tempo-matching and clever editing. They often show up during Kline's weekday show.

"People say, 'Aren't you a little worried?'" Kline said. "You're out there with soul, and you're playing brand-new pop and punk. How can you get that all into an hour? Well, listen to one mash-up. It's the entire spectrum of music."

"Confluence of Giants," a popular track by San Francisco-based DJ Earthworm, combines David Bowie, Queen and Steve Miller with the bass line to Steely Dan's "Do It Again." Juneau's DJ AstronoMAR has also been well-received. His mash-up of John Cougar Mellencamp's "Pink Houses" and Usher's "Yeah" is especially popular.

"Of the calls I get, AstronoMAR is the one that people have asked about," Kline said. "John Cougar Mellencamp and Usher. You would never think that would work. He made it funky."

"The things I mash-up I pick from the farthest end of each spectrum," AstronoMAR said. "I try and do justice to both songs so each track gets a chance to shine. It's totally absurd, but it works."

While KRNN (102.7) is mostly local, live volunteer programming, KXLL is staying predominantly to the mix. The exception is Kline's weekday 3-6 p.m. show, "An Excellent Afternoon," and Eric Caldwell's "80's Nation," 8-11 p.m. Fridays.

The rest is either random selections from the library, or syndicated programming from the Santa Monica-based public radio station KCRW. While there are no immediate plans to hire volunteers to host programs, Kline is looking for people to help with production, voice-tracking and managing and building the library.