Happy that exec didn’t hail a taxi

FOR singer-songwriter Susan Cagle, the word “underground” doesn’t so much describe her sound as the physical space where she refined her commingling of rock, soul, country and world music: the New York subway system. On the platform of Manhattan’s 34th Street train line, to be specific.

“Late at night, there were such amazing acoustics,” Cagle says. “You could hear your voice just echoing off the walls of the subway.”

A busker since she was 3 who spent her life touring the world with her next of kin -- Cagle’s mother, father and 10 siblings formed a kind of Partridge Family of roving street performers -- the 25-year-old musician opened her guitar case for tips and began performing at the Penn Station subway stop in 2001. She gained a cultish following among commuters, selling more than 30,000 homemade CDs and pulling in $1,000 to $2,000 a day at locations including Union Square station and the 42nd Street shuttle stop at Grand Central Station.

And in one of those only-in-New York twists of serendipity, she was discovered there by record producer Jay Levine (who also plucked Canadian rock-soul singer Fefe Dobson from obscurity). He helped Cagle land a major label deal with Sony BMG. And her debut album, fittingly titled “The Subway Sessions,” hits stores in late May on Lefthook/Columbia Records.

“I feel like I’ve been blessed,” she says. “I’ve been hustling and working hard since Day One.”

Which begs the question: Is going underground a better route to pop stardom than “American Idol”?

“I don’t recommend going down into the subway,” Cagle says. “What I recommend is not sitting on your [backside] and waiting for someone to do things for you. Figure out how to work it out yourself and get yourself together.”

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Like the roaming gnome, but shiny

CALL it imperfect timing, but with controversy over Sony’s XCP copy-protection software still percolating and a class-action lawsuit moving forward (the media conglomerate is accused of embedding spyware on millions of CDs), this is an awkward time to turn a “traceable” compact disc into a marketing hook.

But try telling that to U.K. adult-contemporary singer Rob Reynolds and his London-based indie label, Invisible Hands. They have distributed several thousand CDs containing songs from the pop-soul crooner’s 2004 album, “Sightseeing,” for free with instructions spelled out squarely on the cover: “listen to me, copy me, MP3 me, and then leave me on a train, aeroplane or in a cafe or venue.”

The idea is for fans, the record company and the artist to be able to track the discs’ travels. Each CD is numbered and listeners can log on to Reynolds’ website (www.robreynolds.co.uk) to discuss on an Internet bulletin board where they found it and what they think of the music.

“The best way to break an artist is through word of mouth,” explains Charles Kennedy, Invisible Hands’ owner and managing director. “You create an awareness and then everything else follows. The point is to make a dent in popular culture.”

Seems to be working so far. Kennedy says sales of “Sightseeing” have doubled on Amazon.com since the traceable CDs went into circulation (he declines to give exact figures, however). And according to the bulletin board, Reynolds’ discs have popped up from Beirut to Buenos Aires -- one well-traveled fan reported encountering the CD in Tokyo and then seeing another copy, three days later, in Paris.

“Record companies’ business models have got to change,” Kennedy insists. “Profits are falling, advertising no longer works. You’ve got to change your source of revenue. We’re giving away music but then you can still sell it in ads, films and on TV. Or you make your money through selling T-shirts and giving concerts.”

Although the response to Reynolds’ music has been overwhelmingly positive, the public forum also has opened up the singer-songwriter to barbs.

“One guy wrote on the bulletin board, ‘This sounds like Michael Bolton meets Satan,’ ” Kennedy says. “Rob was like, ‘Take [the posting] down!’ But I said, ‘You’ve got to keep it on there.’ This isn’t some corporately stage-managed thing.”

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Sovereign empire sees lots of visitors

SINCE being signed to Island Def Jam by label head Jay-Z last year, bratty white British female rap phenom (there’s a mouthful) Lady Sovereign has been hard at work on her eagerly awaited major label debut, enlisting an eclectic roster of production whizzes.

Among them: U.K. hip-house duo Basement Jaxx and Beastie Boy Ad-Rock (who also produced a remix on Sov’s “Vertically Challenged” EP). And next week, the London-born MC will meet up with hip-hop’s Midas-touch songwriting-production team, the Neptunes, in Miami.