Earth, Wind & Fire closed out the '70s on an incredible hot streak that saw the band forging a chain of gold and platinum records stretching back to 1973's 'Head to the Sky,' as well as some of the most intelligently crafted -- and danceable -- hit singles of the decade. They took a short break for 1978's 'The Best of Earth, Wind & Fire, Vol. 1,' but as they proved the following year with 'I Am,' that didn't mean they were running out of steam.

The band's ninth studio album, 'I Am' arrived in stores in June of 1979, and picked up right where 1977's 'All 'n All' left off -- which is to say that it found Earth, Wind & Fire delivering yet another potent dose of their finely calibrated blend of soul, R&B, pop, and rock. Smooth without falling prey to an overdose of studio polish and dense without being overly busy, the nine-song collection strengthened the group's roots in sweaty, horn-fueled funk while still making room for the popular sounds of the day, and that expansive attitude paid off in spades: the record's widest crossover reaches were its biggest singles, including the massive Grammy-winning disco smash 'Boogie Wonderland' (recorded with the Emotions) and the pillow-soft pop ballad 'After the Love Is Gone' (co-written by future Chicago member Bill Champlin).

Watch Earth, Wind & Fire Perform 'Boogie Wonderland'

As far as bassist Verdine White was concerned, the band was just doing what it had always done: Grow. "The concept behind this album is quite simple," he told Blues & Soul in the summer of 1979. "It's all about music -- just that. It's an ongoing extension of the musical directions we've been taking up to this point. We put a lot more music into it -- it's fuller perhaps -- and it's an amalgam of the different styles we've been associated with up until now. We didn't actually do anything major to make it different; we just went in there and did what we always try to do: play our behinds off."

Reflecting on the crossover success enjoyed by recent singles such as 'September' and their cover of the Beatles' 'Got to Get You Into My Life,' White continued, "We didn't plan to 'go pop.' It's just that the musical direction we've been taking resulted in music that appealed to a larger pop audience than maybe some of our other recordings did. It's like 'Boogie Wonderland': Maybe a lot of people didn't expect us to come from there, but we want to always reflect what the public wants and provide good music. And the sophisticated approach that's involved in 'Boogie Wonderland' doesn't make it just ordinary disco."

Of course, as longtime fans were already aware, constant change had been a hallmark of EW&F's journey from the beginning. Founded by former session drummer Maurice White, the band started out as a Chicago collective called the Salty Peppers before White's migration to Los Angeles prompted a lineup overhaul and a name change. The newly rechristened Earth, Wind & Fire released a pair of critically well-received albums on Warner Bros., but disappointing sales dogged the young group; as White later argued, "The music was far too advanced for the time. Most of the people that heard us then thought we were a white group. They had no idea we were a black group." When the band re-emerged in the fall of 1972 with their third LP, 'Last Days and Time,' they were finally on their way to perfecting the sound that would shortly fuel their rise to prominence.

All this time in the trenches helped edge the band's sound closer to the mainstream, but White insisted he was less concerned with record sales than with providing what he deemed "a service to mankind." Explaining the group's almost relentlessly positive lyrics, he mused, "Music is medicine. It's soothing and it cools you out. Many people have hard and tiring lives, and the positive intensity of this music is intended to serve them. It also exposes them to new things, beautiful things. Everybody knows about pain. The blues is about a certain generation. I heard enough of the blues from my mother and my grand­mother to last me a lifetime."

Not that White was willing to turn his back entirely on the blues. As he explained in a 1978 interview, the music was a huge part of the background and training that helped make him so uniquely qualified to lead one of the biggest bands of the '70s. "Everybody was playing rock and roll, and I wanted to play jazz. I wanted to learn other things," he said of his days playing in Memphis. "But one thing (about) Memphis (that) was so good for me was that it taught me to express myself from a feeling standpoint. You see, I played with a lot of blues bands, and so I learned to play with a lot of feeling and having that embedded inside me helped a great deal because that is something that people search for forever and can't find. Music has to have a feeling, and that is something that has followed me into my productions. And so, in whatever I do, I always resort back to what I learned in Memphis."

Watch Earth, Wind & Fire Perform 'After the Love is Gone'

That Memphis influence was far from the most obvious component in Earth, Wind & Fire's sound by the time 'I Am' arrived, but not because White was turning his back on the past; in fact, the band was running on all cylinders, distilling its assorted influences to create music that seemed to dictate and incorporate current trends in equal measure. The album ultimately peaked at No. 3 on the pop charts on its way to a double platinum sales certification, leading into a world tour that found EW&F operating at peak efficiency while bringing their intricate stage show (which included Verdine White playing a levitating bass solo) to bigger crowds than ever -- and for Maurice, it was really all about those fans. "Just to make people happy with my music is the goal. To help people at their weak moment, if it just takes one word to bring a smile to people, then I'm satisfied," he insisted. "Music is the greatest power I could have ever had and I feel very fortunate that I have been gifted with that power."

That didn't mean the group was willing to settle for smiles -- and as hot as Earth, Wind & Fire were as the '80s peeked over the horizon, Verdine insisted that the band members still weren't satisfied. "We won't be happy until we sell 15 million records and up!" he laughed. "If Fleetwood Mac can do it, we know we can, because our music is as good as anyone else's that's out there. Sure, it's great to reach three million people, but we know just how many people we could reach, and we won't be satisfied until we do. So you can see, we're not even halfway to where we want to be yet."

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