Why are Philadelphians so obsessed with the band Yes?

You want a great love affair? Forget Kanye and Kim, or Jay-Z and Beyoncé. We're talking 50 years. We're talking deep, unbreakable love. We're talking progressive-rock titans Yes and the Delaware Valley.

Since the turn of the 1970s, there has, arguably, been no American city more passionate about the British band whose sonic calling cards have always been complex, turn-on-a-dime arrangements, heavenly vocal harmonies, virtuoso instrumental work, and often-obscure lyrics with a decidedly spiritual bent.

And, as fans around the globe spend this year celebrating the 50th anniversary of the original lineup's creation, those here in Philadelphia and its environs can take pride in their role in the group's decades-spanning success.

"Over the '70s, it became more and more apparent that there was a central place for Yes — on the East Coast, anyway — and it was Philadelphia," said guitarist Steve Howe during a recent chat.

Howe, who joined Yes in 1970, will be at Tropicana Atlantic City on Saturday and at Fishtown's Fillmore July 20 and 21 as part of his band's "#YES 50: Celebrating 50 Years of Yes" tour (in addition to the two Philadelphia concerts, there's a Yes fan fest the day of the July 20th show). He'll be accompanied by drummer Alan White, whose membership dates to 1972 and Yes' first Philly headlining gig (a three-band Spectrum bill opened by a then-brand-new country rock outfit called The Eagles); keyboardist Geoff Downes; bassist Billy Sherwood (who replaced bassist/group cofounder Chris Squire after the man affectionately known as "The Fish" died of cancer in 2015); and lead singer Jon Davison, an aural clone of original front man and lyricist Jon Anderson.

Anderson, incidentally, fronts the band branded as Anderson, (Trevor) Rabin and (Rick) Wakeman or, more familiarly, ARW. That combo is also on a celebratory road trip dubbed "Quintessential Yes: The 50^th Anniversary Tour;" local dates aren't expected until early next year.

>> READ MORE:  Rick Wakeman talks ARW

(The reasons for the existence of two acts playing "Yessongs" is complex and confusing and space limitations prohibit a cogent explanation. Suffice it to say lawyers have been involved.)

Howe suggested the group's rabid support here in Philly "was partly due to the incredible support we had from people like Ed Sciaky and his station [WMMR-FM], but also due to the intensity and love for our music that we discovered there. We were obviously delighted."

Working at WMMR in the era when so-called "underground" stations allowed their on-air personalities to choose the tracks they played, Sciaky— who also famously championed Bruce Springsteen and Billy Joel in the earliest days of their careers — was a conduit to the music-obsessed masses whose lives often hinged on the newest, hippest releases.

According to Sciaky's widow, Judy, Yes' unique sonic blueprint deeply resonated within her late husband from the first time he heard the group's music.

"When he played the first Yes album, it just blew him away," she recalled. "The music just hit him. It was the power of it. It was the eclectic combination of the genres, he just loved the sound. He loved the spirituality, the power and the melody. He just fell in love with it."

Judy Sciaky, who identified Yes' epic, 1973 double-album, Tales From Topographic Oceans as Ed's favorite, is gratified that so many years after his death, his band-connected legacy remains. "I don't know this for a fact, but I would bet that Philadelphia is still their strongest city. And that was absolutely Ed. He was a fanatic who just wanted to get their music out there to as many people as possible. He definitely turned Philly into 'Yesadelphia.' "

But Ed Sciaky played records by a number of artists who are barely remembered today. What was it in the group's sound that pulled in local music fans and became, for so many, a lifelong passion?

One of those mega-Yes-heads is Michael Smerconish, the Sirius/XM and CNN host and Inquirer columnist. It was 1977's Going For the One that caused Smerconish to be bitten by the Yes bug.

"The mystery of what it all meant, I think," the pundit said via email when asked what it was about Yes that first grabbed him. "Remember, this was an era when many of us spent far too much time in our bedrooms reading liner notes, convinced that the rock gods had all the answers. Figuring out what those songs meant was half the fun. And the Roger Dean [album cover] art made it a full presentation that you don't see today. And, I wasn't alone. It really was a Philly thing. We were all into Yes then. I still am, but I don't like the split in the band and I've stayed loyal to [Anderson]."

If there is a milestone moment in the Yes/Philly love affair, it is June 12, 1976. The relationship was cemented forever when Yes and Peter Frampton (then rocketing to megastardom on the strength of his out-of-the-blue smash live album, Frampton Comes Alive) co-headlined a concert at the former JFK Stadium, where the Wells Fargo Center now stands.

>> READ MORE: Electric Factory turns 50: How the concert business was created in Philadelphia

Larry Magid of Electric Factory Concerts was the show's promoter. He also was the first to book Yes in the area, in 1971 at Wildwood Convention Hall, opening for Jethro Tull.

Magid said that when he first started producing concerts in the late 1960s, "People would come to concerts just because it was a concert. Yes, to me, was one of the first recognizable English groups in that third English wave that came over. It just took off."

More than 40 years later, the JFK show — which also featured British singer Gary Wright and the long-forgotten Pousette-Dart Band — is often recalled for the massive audience that shoehorned its way into the now-defunct stadium.

Magid put the "official" attendance at 80,000, but, he said, the actual attendance was "at least" 100,000. The discrepancy, he noted was because "we had a partner we didn't realize we had." Ticket takers resold the passes once they took them from concertgoers.

Magid also spoke of the near-fist fight between Frampton's manager, Dee Anthony, and his Yes counterpart, Brian Lane, that erupted backstage after a banner plane trumpeting Yes flew during Frampton's late-afternoon set. And he described how the summerlike daytime weather took an unexpectedly chilly plunge after dark, causing barely dressed fans pummeled by a day of sunburn and alcohol indulgence to seek warmth in fires set throughout the predominantly wooden stadium while Yes was onstage.

"You can't do a show like that without remembering something," Howe said when asked about his memories of the day.

"That was a standout show. Peter and Yes linked arms and went out together. He was riding the crest of a wave, and we were, in a way, riding the crest of a much longer wave with a much slower curve, if you like. The craziness [of the event] doesn't really interest me at all, but I guess it was there. But it was exciting. It was a big show. We have done others, but that was a pretty big one, I got to say."

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