2024 marks the 50th anniversary of the song that gave a name to an influential musical phenomena; a song that became an anthem for Philadelphia and for an entire era of Black art and culture. 

Written and produced by Kenneth Gamble and Leon Huff, "T.S.O.P. (The Sound of Philadelphia)" represented the pinnacle of what is known as Philadelphia soul — also called orchestral soul, symphonic soul, or in the words of James Brown trombonist Fred Wesley "putting the bow tie on funk." It’s largely associated with Philadelphia International Records, a label founded and owned by Gamble and Huff in 1971. 

Outside of Gamble and Huff, Philadelphia soul was also engineered by a suite of songwriters and producers like Thom Bell, Dexter Wansel, Gene McFadden, John Whitehead, and Bunny Sigler. Though Philadelphia has long been a musical city — famed 1950s music variety show "American Bandstand" started as a local Philadelphia broadcast program — the sound of Philadelphia gave it a definitive face. 

Philadelphia soul was a transitional, experimental genre that reflected the similarly transitional and experimental culture of the ‘70s. For better or worse, Motown is culturally associated with the fizzy optimism and respectability politics of the integrationist '60s. Disco is pegged as the defining sound of the hedonist, glamorous, sexually liberated late '70s. Philadelphia soul bridged the gap, with an emphasis on self-love, self-determination, and community as the Black struggle raged on.. Philadelphia soul was the sound of a community in motion. 

At the musical foundation of the sound of Philadelphia was the blend of traditional soul and classical influences, as its architects used the cinematic drama of both to express the turbulent emotions of the times through music. Philadelphia soul dominated commercially and culturally for about 10 years before fizzling out of the mainstream, and its disregard for strict genre conventions and emphasis on experimentation paved the way for a sonically diverse R&B landscape. Read on for 10 songs that defined the innovative Sound of Philadelphia.

The Delfonics - "La-La Means I Love You" (1968)

Songwriter and producer Thom Bell — who went on to win the very first GRAMMY Award for Producer Of The Year — helped to put the Philadelphia soul movement in motion with his work with the Delfonics. Bell’s penchant for imbuing soul with the larger-than-life opulence of full orchestral arrangements stemmed from his childhood, as he grew up strictly listening to classical music while he trained to be a concert pianist. 

Bell’s writing and producing partnership with the Delfonics’ lead singer co-songwriter William Hart was one of the first bridges between traditional soul and what would become Philly sound, with songs like the GRAMMY-winning "Didn’t I (Blow Your Mind This Time)" featuring an eclectic blend of instruments like bells, an electric sitar, and a prominent Alpine horn. "Ready or Not (You Can’t Hide from Love)" boasted one of the most bombastic string and horn intros music has ever heard, making it extremely popular song for sampling as it provided the basis for songs like the Fugees’ "Ready or Not," Missy Elliott’s "Sock it 2 Me," and Bridgit Mendler’s "Ready or Not." 

But the Delfonics’ finest moment was their breezy breakout hit "La-La Means I Love You," a homage to ‘50s love songs and doo-wop inflected Motown. Bell’s grandiose string arrangement gives the song a fairytale feel to match the dreamy "la-las." Rounded out by Hart’s buoyant lyrical emphasis ("many guys have come to you / with a line that isn’t true"), "La-La Means I Love You" kicked off Bell’s illustrious writing, producing, and arranging career.

Billy Paul - "Me and Mrs. Jones" (1972)

Billy Paul’s GRAMMY-winning "Me and Mrs. Jones" is peak Philadelphia soul. Released just one year after Philadelphia International Records was established, the perfect storm of Paul’s jazz-trained vocals, a mesmerizing story, and a full Thom Bell orchestral arrangement made for one of the greatest soul songs of all time. It subverts the usual franticness of "cheating anthems" by moving at a luxuriously slow tempo, relishing in Paul’s vocal vamping and the instruments that glide along with him. It’s a song that epitomizes drama, with a jazzy clarinet, crescendoing horns, and syncopated hi-hats creating an intensity that makes the utter silence when Paul belts into the chorus ever more piercing.

The rest of the songs on the album 360 Degrees of Billy Paul are all covers or socially conscious songs; Paul’s stellar bluesy second single "Am I Black Enough For You?" and album tracks "Brown Baby" and "I’m Just a Prisoner" are among the best to come out of Philadelphia soul. "I’m Just a Prisoner" is a stunning reflection on mass incarceration and injustice, with lyrics by Gamble, Bunny Sigler and Phil Hurtt: "Got no trial in sight / This justice they all talk about just ain't right / Has everybody forgotten about me? / Will I ever, ever, ever be free?" 

In his documentary Am I Black Enough For You?, Paul discusses how his decision to lean into songs about Black empowerment and social issues ended up undoing the mainstream success he achieved with "Me and Mrs. Jones" as audiences turned their back on him. 

The O’Jays - "Back Stabbers" (1972)

Back Stabbers brought the O’Jays a Billboard No. 1 song with "Love Train," an iconic ode to world peace and unity that made them synonymous with the success of Philadelphia soul. "Love Train" and the album’s self-titled first single "Back Stabbers" are the yin and yang of the sound, as the mysterious and moody "Back Stabbers" represented its early penchant for creative experimentation. 

"Back Stabbers'' adopts influences from the funky, psychedelic Norman Whitfield sound that was defining Motown in the ‘70s with songs like "Papa Was A Rolling Stone" and "Smiling Faces Sometimes," the latter of which is quoted in "Back Stabbers." In its extended introduction, a thrilling piano gives way to conga and bongo drums, jazzy guitar, and organ, all underscored by sinister-sounding strings and horns. The O’Jays’ Eddie Levert and William Powell engage in a frantic back-and-forth throughout, building the feelings of frenzy. 

As much about the state of the world — one that was in the midst of the Watergate scandal, Vietnam War and mass urban decay — as it is about relationship paranoia, "Backstabbers" is an ode to betrayal, with evocative lyrics like "the blades are long, clenched tight in their fists / Aimin' straight at your back, and I don't think they'll miss." 

The Stylistics - "People Make the World Go Round" (1973)

Philadelphia soul is often called a "producer’s genre," but its iconic lyrics can’t be underrated — many of which came from the poetic imagination of Linda Creed, Thom Bell’s most frequent collaborator. The two primarily worked together on songs for the groups the Spinners and the Stylistics, cranking out R&B staples like "The Rubberband Man" and "You Are Everything." 

Bell instantly hit a creative stride with the Stylistics largely because of his love of lead singer Russell Thompkins Jr. 's tenor voice. In 2023, Rolling Stone included Thompkins Jr. on their 200 Best Singers of All Time list, affirming "[Thompkins Jr.’s] supernally precise singing defined R&B romanticism and gave the falsetto tradition new heights to hit." Bell dialed up his penchant for both sweetness and experimentation for the Stylistics’ production, such as on the Creed-written "You Make Me Feel Brand New" which combines Thompkins Jr’s falsetto and a hypnotic electric sitar for a spiritual feeling. 

Bell and Creed' creative partnership reached its experimental peak with the Stylistics’ "People Make The World Go Round." Creed’s lyrics leaned into poetic commentary on greed and exploitation, like "Wall Street losin' dough on every share, they're blamin' it on longer hair / big men smokin' in their easy chair, on a fat cigar without a care." To complement her experimentation, on top of Bell’s usual stack of orchestration, the song featured wind chimes, marimba, xylophone, and a flute solo. The song’s melody followed a stilted syncopation that reflected the intensity of the subject matter, structuring Thompkins Jr.'s falsetto into a meandering rhythm that turned the usually romantic voice into something haunting.

MFSB - "T.S.O.P. (The Sound of Philadelphia)" (1973)

The literal "sound" of Philadelphia soul is the sound of MFSB (Mother Father Sister Brother), the house band for Philadelphia International Records and the instrumentalists on the vast majority of Philadelphia soul songs. MFSB was a group of 30-plus session musicians at Sigma Sound Studios in Philadelphia, where the majority of Gamble, Huff, Bell and co.’s songs were recorded by engineer Joe Tarsia. 

The rich, symphonic sounds that define Philadelphia soul were brought to life by MFSB, and once they finally claimed the spotlight as a recording act they produced the genre’s most important entry. In 1973 MFSB released "T.S.O.P. (The Sound of Philadelphia)," a song Don Cornelius asked Gamble and Huff to write to become the new theme song for "Soul Train." The result indeed feels like an uplifting, exhilarating train ride.

MFSB had their moment to shine and they delivered; from Zach Zachery’s wailing saxophone outro to Lenny Pakula’s jubilant organ to a dominant drum rhythm by Earl Young, who would go on to be called the father of disco drums and win a GRAMMYfor "Disco Inferno" as a member of the Trammps. The song is tied together with a harmonious bow by the vocals of girl group the Three Degrees, marking the start of their prolific run at Philadelphia International Records with just two lyrics: "people all over the world" and "let’s get it on, it’s time to get down." 

The Three Degrees - "If and When" (1973)

The Three Degrees’ self-titled first album on Philadelphia International Records was released in late 1973, hot off of the success of "T.S.O.P.." At a time when the girl group boom had dried up, the Three Degrees soared to international stardom. (The now-King of England still loves their music, and invited them to sing and party with him on his 30th birthday.) 

The biggest hit on The Three Degrees was "When Will I See You Again," a dreamy song that follows a fairly straightforward Gamble and Huff formula which, like "T.S.O.P.," treats the Three Degrees’ vocals like one of many beautiful instruments in the mix, rather than the centerpiece. The song trails off into a set of harmonies that scratch the surface of what the group is capable of when given the space to shine. 

They shine brightest on "If and When," a wistful, intense ballad that showcases the group as a powerhouse vocal unit. Every second of the song’s sound is emotive and wholly centered on the Three Degrees, with the ornate orchestration and fanfares serving to build up the vocal dynamics rather than the other way around. Around the halfway mark of the song, the brash chorus gives way to a four minute outro where the group erupts into a vocal supernova. The Three Degrees give their finest vocal performance for those lasting minutes of harmonic variations on the chorus, swelling and stretching and blending their voices as elegantly as any orchestra. 

The O’Jays - "For The Love of Money" (1973)

The O’Jays were often the conduit for Gamble & Huff’s philosophies and politics, and the messages in their music became most poignant on 1973’s Ship Ahoy. Ship Ahoy charts historical injustice to diagnose what Gamble and Huff identified as issues still plaguing the Black community. Ship Ahoy’s title track is a nine minute epic pointing to the original sin of Black America, the transatlantic slave trade. Bookended by the sounds of waves and whips, "Ship Ahoy" casts a sorrowful, unflinching spotlight on slavery. 

The rest of the album looked at issues like environmental injustice ("This Air I Breathe") and lack of solidarity ("Don’t Call Me Brother"). Love songs sprinkled in between balance between consciousness and optimism, but Gamble and Huff never shied away from the topics they deemed most important. 

The album’s crown jewel is "For The Love of Money," a moody song about the evils of materialism, lamenting that "people can't even walk the street / because they never know who in the world they're gonna beat for that mean, green almighty dollar." In one of their first big creative departures, Gamble and Huff replaced their typical lovely strings with a funky bass, topped off with background vocal chants warped by echo effects to hammer home the ominousness. Trumpets that sound more like warning sirens, mark the brightest sounds on the song.

Teddy Pendergrass - "When Somebody Loves You Back" (1978)

Teddy Pendergrass’ rise to stardom was a Cinderella story, having been initially hired as a drummer for the group Harold Melvin and the Blue Notes before joining the group as a vocalist. Once the group joined Philadelphia International Records, it became clear to Gamble and Huff that Pendergrass had a standout voice that was perfectly suited to their style and he essentially became the vocal headliner of Harold Melvin and the Blue Notes. 

With a voice Rolling Stone listed as the 42nd greatest of all time, Pendergrass was the lead on all of the group’s biggest hits, such as "If You Don’t Know Me By Now," "Wake Up Everybody," and "The Love I Lost." 

A solo breakout was inevitable, and Pendergrass went on to become the first Black artist to have five consecutive platinum albums. Debuting in the midst of disco’s late ‘70s reign, Gamble, Huff, and Pendergrass leaned heavier into pure soul than many of their peers. Pendergrass’ baritone voice balanced Gamble and Huff’s ornamental productions with sensual grit. Combined with Pendergrass’ abundance of natural charm and charisma, his stream of bedroom songs like "Close the Door," "Come Go With Me," and "Turn Off The Lights" made Pendergrass into a prolific sex symbol. But the more saccharine "When Somebody Loves You Back" showcases his musical partnership best, as Gamble and Huff amplify a feeling of dizzying elation with playful horns and a whirlwind of strings cushioning Pendergrass’ giddy celebration of loving and being loved. 

McFadden & Whitehead - "Ain't No Stopping Us Now" (1979)

Gene McFadden and John Whitehead mastered the art of putting the "message in the music," and proved to be two of the greatest lyricists of Philadelphia soul. At their sentimental best they co-wrote The Intruders’  "I’ll Always Love My Mama" and Harold Melvin and the Blue Notes’ "Wake Up Everybody," channeling their cynical sides for Harold Melvin and the Blue Notes’ "Bad Luck" and the O’Jays "Back Stabbers." Their songwriting specialty was storytelling, and eventually they wanted to be the ones singing the stories. 

McFadden & Whitehead’s first single off their debut album was "Ain’t No Stopping Us Now," where Philadelphia soul explicitly dovetails into disco, as peppy drum kicks and a synthy keyboard augment the sound. One of the most optimistic songs of all time, "Ain’t No Stopping Us Now" is naturally anthemic, lending itself well to sports and other pursuits of victory with lyrics like "we won't let nothing hold us back, we're puttin' ourselves together, we're polishing up our act. / And if you've ever been held down before, I know you refuse to be held down any more." It became not only their signature hit but a national anthem for Black American prosperity, and was used prominently on Barack Obama’s 2008 presidential campaign trail. 

The Jones Girls - "Nights Over Egypt" (1981)

One of Philadelphia International Records’ most prolific songwriters and producers was Dexter Wansel, who created a cosmic fantasyland in his musical corner of the world. As he stated in 2018, "I did a lot of instrumentation that was experimental. I’ve always thought of outer space as being my guideline." Wansel’s own underrated debut album on Philadelphia International Records, Life on Mars, layered warbling synthesizers on top of funk and jazz fusion to convey his take on cosmic liberation. Its standout "Theme from the Planets" can be heard in hundreds of samples, notably in the drums and bass line of Dido’s "Thank You" (and thus in Eminem’s "Stan").

Wansel was then perfectly positioned for Philadelphia soul’s transition from classical influences and disco cheer towards the slicker, more future-focused R&B of the 1980s. His collaborations with the Jones Girls were some of the most successful examples of this transition, with vocal dexterity that made them as suited to symphonies as they were to funk. Wansel and co-writer Cynthia Biggs channeled the Egyptology influences that were prominent in Afrofuturist funk for the Jones Girls’ "Nights Over Egypt." A song that married strings and harps with groovy jazz fusion, it became emblematic of the quiet storm subgenre that boomed in the early ‘80s. 

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