Those formative teenage years set a tone for an entire lifetime. Personal battles, career goals, ideas about love - figuring out how all of that will play out during adulthood is one of the big chores of those high-school years. Setting the backdrop for much of that inner struggle is the music - it's the soundtrack of one's identity, the bond that glues generations.

That idea is at the heart of Ronnie Milsap's Summer #17, an album that explores the influences on a musician who built a Hall of Fame-caliber career, who became one of the most influential voices in country music's storied history.

Much has been made about how such new country acts as Eric Church, The Band Perry and Luke Bryan have fused elements of pop music's past with the country core to create a new wave of sound. But Milsap set the standard for thinking outside of country's proverbial box.

Milsap emulated James Taylor in his vocal approach to "(There's) No Gettin' Over Me," a #1 record in country and pop; hooked into the instructions he got playing piano on Elvis Presley sessions to build the sound of "Smoky Mountain Rain," another major crossover hit; and recorded an entire album of songs made famous by late Country Music Hall of Famer Jim Reeves.

Milsap used pop, rock and R&B elements to test country's borders, and did so in a way that connected fiercely with the music-buying public. He compiled 40 #1 country hits. Milsap's sales accrued eight gold albums; his Greatest Hits made him one of the first acts in any genre to obtain double-platinum status after the RIAA introduced the multi-platinum honor in 1984.

The industry responded as positively as the public. Milsap won six Grammys; eight Country Music Association awards, including Entertainer of the Year; and four more Academy of Country Music trophies, including the lifetime honor, the Pioneer Award.

Milsap helped establish the boundaries for what country could be - then pushed them further, most notably in his rockin' 1983 single "Stranger In My House." Milsap had guitarist Bruce Dees infuse bits of Grand Funk's classic-rock landmark "We're An American Band" into the solo section, a risky, envelope-busting decision that had many radio stations of the time balking.

Time would prove Milsap's artistic judgment to be correct. Even resistant stations eventually added it; "Stranger" won a Best Country Song Grammy for songwriter Mike Reid, and music fans - most of whom care little about creative boxes - responded enthusiastically.

"When we play live shows today, people still want that song," Milsap marvels.

In fact, many of country's newest hitmakers are still applying ideals that are key to Milsap's legacy. Blake Shelton, an Entertainer of the Year winner and celebrity coach on NBC's The Voice, specifically channeled Milsap while working on a song for his Red River Blue album. Vocalists such as Eric Church, Billy Currington and Lady Antebellum's Charles Kelley have renewed the blue-eyed-soul stance that Milsap brought to country. And 22-year-old heart throb Hunter Hayes, when he made his headlining debut at Nashville's historic Ryman Auditorium in fall 2013, brought out Milsap as a special guest to collaborate on that once-controversial song "Stranger In My House."

Milsap clearly influenced the direction of modern country music, and Summer #17 subtly demonstrates the multiple sounds and styles that helped formulate his own development. The album borrows from traditional pop (Tommy Edwards' "It's All In The Game," Bobby Darin's "Mack The Knife"), classic soul (Wilson Pickett's "Mustang Sally," Jimmy Ruffin's "What Becomes Of The Broken Hearted") and - of course - old-school country (Hank Williams' "I Can't Help It If I'm Still In Love With You").

They were important songs during the years in which Milsap built his musical persona, and his relationship to them is similar to the reactions nearly every fan of popular music has for their own set of influential titles.

"Somebody can talk about a song, or I can hear a song right now on Sirius XM in my car and immediately I know what summer it was or when it came out," he says.

That's particularly true for "Georgia On My Mind," a song Milsap performed when he was inducted into the Georgia Music Hall of Fame in 1990. Ray Charles launched the definitive version of that standard into public consciousness as Milsap was living out his own summer #17.

Charles would appropriately have a major impact on Milsap's career choice. Through two editions of his album Modern Sounds in Country & Western Music, Charles showed how elastic great country songs could be. At a 1963 concert in Atlanta, Charles encouraged Milsap to pursue music - against the counsel of his high school and college instructors - setting the stage for Milsap's own versatile entertainment journey.

"I was playing some songs at a piano in his dressing room," Milsap recalls, "and he said, 'Well, it sounds like that's where your heart is, and that's what you should follow.' That sounded to me like an endorsement from Ray Charles. He said, 'Just be around it. Absorb it every day of your life. Live and breath it every day.' That's exactly what I did."

Milsap had been living music almost from the start. Born in Robbinsville, North Carolina, at the edge of the Smoky Mountains, he was enveloped in his early years by country - the region was crucial to such history-makers as Jimmie Rodgers, Chet Atkins and Dolly Parton. Milsap subsequently received classical training at the Governor Morehead School for the Blind in Raleigh, though he notoriously frustrated his teachers by banging out Jerry Lee Lewis and Little Richard rock & roll on the keyboard when he was supposed to be practicing Mozart and Beethoven.

Milsap did some recording while attending college in the Atlanta area even before that backstage meeting with Charles, and in the wake of Charles' encouragement, Milsap found his way onto New York's Scepter label, where the roster also included Dionne Warwick and Chuck Jackson. One of Milsap's singles, Ashford & Simpson's composition "Never Had It So Good," became a Top 5 R&B hit.

Milsap's music continued to connect him with future Hall of Famers and key figures. He moved to Memphis, working frequently with producer Chips Moman (Neil Diamond, The Box Tops), who put him to work on several Elvis Presley sessions. Specific instructions from Elvis during recording on "Kentucky Rain" - "Hey, more thunder on the piano, Milsap!" - still ring in Ronnie's ears.

During that time, he performed on Los Angeles' Sunset Strip, first with J.J. Cale, then on his own. One night his audience included future Country Hall of Famer Charley Pride, who encouraged Milsap to try his hand in Music City. Opportunity came when he was invited to become the house singer at Nashville's King of the Road Motor Inn, owned by Hall of Famer Roger Miller. Within weeks, Milsap signed a management deal with Pride's manager, Jack D. Johnson, and recorded his first hits for RCA.

That began a remarkable string in which Milsap nabbed at least one Top 10 single annually for 20 straight years. Those songs connected him to some of the most significant writers of his generation - Kris Kristofferson ("Please Don't Tell Me How The Story Ends"), Burt Bacharach ("Any Day Now"), Eddie Rabbitt ("Pure Love"), Don Gibson ("I'd Be A Legend In My Time"), Mike Reid ("Inside," "Stranger In This House"), Archie Jordan ("It Was Almost Like A Song") and Hank Cochran ("Don't You Ever Get Tired Of Hurting Me"), to name just a handful.

Milsap earned a reputation for his meticulous recordings. He purchased a Music Row studio from Roy Orbison, renamed it Ground Star Laboratory, and experimented with elaborate keyboard parts, inventive guitar sounds and multi-layered vocals. It was a precursor to the modern recording era, where artists such as Reba McEntire, Martina McBride, Brad Paisley and Steve Wariner have built their own recording facilities. Milsap's former studio - which has been used by Merle Haggard, Ricky Skaggs and Pistol Annies - appropriately still operates today, lovingly re-branded Ronnie's Place.

All of Milsap's trend-setting history as a music maker informs Summer #17. Co-produced with longtime associate Rob Galbraith and Richard Landis, it incorporates the most important genres among his musical influences - country, pop and R&B - closing with "Lost In The Fifties Tonight," reprising his award-winning 1985 #1 that successfully knitted a nostalgic doo-wop storyline with what was then considered a boundary-challenging ballad sound. Mandy Barnett, known for her frequent and critically acclaimed theatrical portrayals of Hall of Famer Patsy Cline, provides a strong female vocal partner on two tracks, including a remake of the Stylistics' "You Make Me Feel Brand New."

That male/female vocal relationship is central to the album's mood. The music from the teen years sets the tone for adulthood, often intertwined with a person's initial experiences with love. Those pangs of innocent romance - and their heart-breaking disappearance - are the backbone of "Summer #17." Love plays a crucial role in every other song on the project, with the exception of Bobby Darrin's jazz-pop mob tale "Mack The Knife."

Love and its mysterious nature are, in fact, a thread that's run through much of the material that's set Milsap apart. An unrepentant series of love songs - "What A Difference You've Made In My Life," "Daydreams About Night Things," "How Do I Turn You On," "She Keeps The Home Fires Burning," "What Goes On When The Sun Goes Down" and "A Woman In Love," among others - became inescapable hits, in part because of Milsap's ability to recognize a great, universal melody. What makes a great melody is as nearly impossible to define as love itself.

"You don't know why love works," says Milsap. "You don't know when you meet somebody and you feel a spark or you feel a connection - did that happen randomly? Or is it something that was predetermined?"

They're the kinds of questions that apply to a Hall of Fame-caliber career: How much of it was effort? How much of it was sheer destiny? Those are also the kind of questions Milsap's not entirely able to answer about his own love life. He married the former Joyce Reeves in 1965, and the couple is still together nearly five decades later, defying general music-business expectations. Whether it's a result of random chance or divine guidance, Ronnie's successful navigation of that primary relationship has fueled an artistic relationship with millions, because what's most important in his life is also a priority in theirs.

"The only thing that really counts, that really matters is love," he says. "That's the only thing that's gonna get me through."

That personal connection with Joyce and his love for music are behind the innovation, the sweat, the creative fire and the elite Hall of Fame-level legacy Ronnie Milsap has developed. The seeds to that fire can be found in Summer #17. They provide a clue to the inspirations Milsap used to reshape the landscape of country with an uncanny daring, helping propel the genre forward from a time when it was dismissed by taste-makers to its current hipster status in American culture.

What the kids are doing today in redefining country is nothing new. They're simply carrying on a master plan Milsap laid down years ago.