A crowd of celebrities and music VIPs descended on legendary Patsy's restaurant in midtown Manhattan last week to mark what would have been Frank Sinatra's 95th birthday. Reporters competed to snag interviews with experts, among them, Livingston resident Charles Granata, one of the country's leading experts on Sinatra's musical life and recordings.

Granata, who has lived here in town for 13 years, is the author of the acclaimed book Sessions With Sinatra, and the producer, engineer and occasional co-host of a weekly Sirius-XM Satellite Radio show on the Siriusly Sinatra channel. He's written extensively about Sinatra, and appears frequently on NPR and PBS to discuss the legend; he's also in demand at music festivals where he keeps audiences rapt with insights into the performer's recording style and techniques.

None of this would be at all surprising if working as a music historian, archivist, producer and writer was Granata's full time job. Instead, it's a major moonlighting pursuit, one which he decided to chase one afternoon 21 years ago.

"I was directing traffic one day," the Livingston police officer explains, "and I just decided: I'm going to write a book about Frank Sinatra. That was 10 years before the book came out, but that was the beginning."

Today, the father of two and member of the Livingston Board of Education is still on the job as a township police officer, currently serving as the force's Accreditation Manager in the Professional Standards Bureau.

When not at his headquarters desk, Granata is often at venues most people wouldn't think of finding an off-duty cop. Often he's holed up in a former barn in his backyard, now a snug studio, office and library. Or, he could in New York, California or Canada working as a producer and consultant (thus far, he's worked on four Grammy-nominated box sets); conducting off-site interviews for the radio show, being interviewed himself, or giving lectures – such as one this fall at the Los Angeles Jazz Festival, examining Sinatra's musical roots, methods and influences.

So how does a boy coming of age in Bloomfield in the 1970s and early 80s develop an unbridled fanaticism for a singer whose career peaked decades before? Granata credits his parents, especially his mother, who exposed him to all kinds of music.

"I was probably the only kid to listen to Frank Sinatra, Beethoven, Latin music, opera, big bands and Led Zeppelin all in one day," he says. "I loved it all – world music, classical, everything."

At a neighborhood garage sale, he scored a trove of old Sinatra LPs in good condition. Granata was especially intrigued by the album covers, one in particular featuring Sinatra looking casual and cool, in front of a full array of studio musicians. It was called "Sinatra Swinging Sessions."

"I was fascinated with the photos, the labeling, the colors. Even then, I wanted to know, what was going on in the studio that day?"

Throughout his 20s, Granata steeped himself in the intricacies of Sinatra's musicianship, and began to collect hard-to-find Sinatra materials – albums issued around the globe, original sheet music, photographs in pristine condition, every 78 Sinatra recorded, rare rehearsal recordings and the gem in the crown: original "transcription discs." The discs, made of aluminum or glass (from the days when records were literally "cut"), are one-of-a-kind recordings of what transpired during production of Sinatra's broadcast radio shows from the 1940s, complete with banter between the singer, musicians, producers, and recording engineers.

At the time, not everyone in Granata's life was particularly enthusiastic about what was then an all-consuming, and expensive, hobby.

"There was a point after we were first married when I had bought a collection of rare transcription discs for about $700, and my wife flipped out," he recalls. "She was worried that we'd never have a house if I kept at it. I said 'trust me.'" She did, and today, Barbara is a strong supporter of her husband's extra-curricular workaholic habits. They do have a house, where they are raising two daughters.

In the late 1980s and early 1990s, word got around the music industry that an unassuming young man in Essex County, New Jersey, had amassed one of the most complete archive of items about Sinatra's recording career ever assembled.

That's when Sony came calling.

About to embark on an extremely ambitious box set of 12 CDS, featuring all of Sinatra's recordings on the Columbia label, the company was in dire need of artwork. At the recording company's Manhattan headquarters, Granata laid a fraction of his collection across a conference table. A stunned music executive hired him on the spot as a creative consultant, to help advise the producer and creative director, plan visuals and collaborate on the 150-page hardcover book included with the set which was released to raves in 1993.

"It was the moment that changed my life," admits Granata, who had a gut feeling his collection and research was important, but was surprised by the overpowering reception to his archival material and the expertise he'd built. "I began to realize that what I was doing might have some cultural or historical value."

By then, Granata had made contact with music historian Will Friedwald, and was soon helping do research for Friedwald's 1995 book Sinatra: The Song is You. Next, Granata proposed his own idea for a Sinatra book, quickly snapped up by Chicago Review Press.

For Sessions with Sinatra: Frank Sinatra and the Art of Recording, Granata wanted to document the musical milieu and human interactions when Sinatra stepped into the studio. He tracked down and interviewed some 200 musicians, producers, and engineers, many by then quite elderly. Others, like Quincy Jones, still prolifically active. His goal, to preserve the nuance of a Sinatra recording session for future generations of music historians and Sinatra fans, led to generous praise from the industry when the book was released in 1999.

Granata then turned his attention to other musical interests. His second book was Wouldn't It Be Nice: Brian Wilson and the Making of the Beach Boys' Pet Sounds (Chicago Review Press, 2003). Next, he was asked by stellar record producer Phil Ramone to collaborate on his memoir, resulting in Making Records: The Scenes Behind the Music (Hyperion, 2007).

"The Ramone book took about three years; I spent a lot of time interviewing and listening to Phil, getting a feel for his (literary) voice. I've been very lucky," Granata says.

Lucky, and a hard worker. He initially met Nancy Sinatra when researching the Columbia box set, and they bonded when she asked him to help with her 1995 book, Frank Sinatra: Am American Legend.  Three years ago the pair came up with the idea for the Sirius radio program called Nancy For Frank. It airs Sunday nights to a legion of rabid listeners, who can't get enough of their banter and musical selections from deep in the Sinatra archives.

The two sometimes record together in person, but most of the time, since Nancy lives in California, they talk and email frequently to plan out shows, meticulously picking over a song list. Then, via special phone and digital hook-ups, they sit at microphones in recording stations on different coasts, chatting back and forth between songs and sometimes interviewing guests.

Some recent ones included Johnny Mathis, James Darren, Twyla Tharp, Steve Wynn and Brian Wilson. Finally, Granata mixes the show and uploads it to Sirius.

His recording set-up is flanked by thousands of CDS, LPs, DVDs and books by and about the musical giants of the 20th century. The more valuable parts of the archive however, are kept in a storage facility in, he jokes, "an undisclosed location." Scattered among the shelves are backstage passes from hundreds of concerts, and photos of Granata with many music superstars.

Yet he remains humble and low-key about hob-knobbing with the elite.

Recently, he was asked by a friend of a friend, if her son, who was interested in a radio career, could tag along on a trip into Sirius Radio's Manhattan headquarters. He readily agreed, but warned they might have to "do a few errands" along the way – those included recording a live interview with Springsteen E Street Band guitarist Steve Van Zandt, a stop at the studio of legendary radio DJ Cousin Brucie, and a quick hello with 1960s rock singer Ronnie Spector.

"I think everything I've done in my life, from the age of two, led me to where I am now," Granata says.

Today, he is developing possible future book projects, but isn't sure (or won't say) which might get green-lighted. Meanwhile, he's working on ideas for a mystery or police novel. It will be set in the music world. Where else?